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1. Field of the Invention
This invention relates generally to brake control systems, and more specifically to an improved vehicle brake control system.
2. Description of the Prior Art
U.S. Pat. No. 3,691,524 relates to a tire inflation monitoring system for monitoring the angular movement of the wheels of a vehicle. By counting the revolutions on each of the wheels and comparing the count with the count from another wheel, it is possible to determine whether or not each wheel has the same diameter. An indicating means is provided for signalling an occupant of the vehicle when a tire thereon is underinflated. A disadvantage of this prior art monitoring system is its lack of sensitivity which precludes its use for operating a meter or indicating differences in wheel revolutions during braking.
U.S. Pat. No. 2,522,139 relates to a frequency responsive system for comparing two alternating current frequencies and creating a third frequency in relation to the difference in the two frequencies to indicate the sense and magnitude of this difference. A disadvantage of this frequency responsive system is that the compared frequencies involved are high and the difference frequency low in relation thereto so that this system is not readily usable in a monitoring system of the type disclosed in U.S. Pat. No. 3,691,524.
U.S. Pat. No. 3,797,893 relates to a brake force control system for vehicles in which a sensor is coordinated with each wheel for detecting its rotational condition. The signals from the sensors actuate inlet and outlet valves when they exceed or drop below certain threshold values so that the brake pressure either increases, remains constant, or decreases. In vehicles with a high center of gravity and especially with a short wheel base, an additional logic circuit connection is provided which decreases the pressure at the front wheel brakes if a signal symbolizing the road traction of the rear wheels does not arrive within a certain time delay.
U.S. Pat. Nos. 3,260,555, 3,482,887 and 3,756,663 are exemplary of anti-skid brake systems having electrical means for sensing the rotational speed of individual wheels. An electrical signal is obtained as a result of a variation in the signal in relation to a predetermined characteristic. The signal is used to automatically operate means for controlling and releasing the braking force on any wheel or number of wheels revolving slower than a desired speed. Although the latter patents all operate satisfactorily for preventing the wheels of a vehicle to skid, none of them are capable, among other things, of determining the prebraking rotational speed ratio of a pair of wheels and by controlling the brake force applied to the wheels maintaining the braking rotational speed ratio substantially equal to the prebraking rotational speed ratio. | {
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Electronic systems and devices such as, but not limited to computer systems, mobile devices and phones, set top boxes, printers, etc. are known to include two or more integrated circuits. An integrated circuit as used may refer to a single integrated circuit or a collection of integrated circuits or integrated circuits. Each integrated circuit may include “logic.” Logic and derivatives of the term logic may include any number of integrated circuit components such as, but not limited to, the transistor. As is known in the art, integrated circuit components, such as transistors, may form logic that is capable of performing a variety of operations. Because an integrated circuit may consist of multiple integrated circuits, as used in this disclosure, references herein to logic may physically bridge or span over one or more integrated circuits or integrated circuit packages. Integrated circuits are known to communication with each other using a variety of signals. As used throughout this disclosure, the term “signal” and all derivatives thereof refer to any suitable analog or digital signal carrying information and/or data. The term signal and its derivatives may also refer to one or more voltage levels as is known in the art. For purposes of clarity, the statements made above are applicable throughout this disclosure.
The integrated circuits have core logic which is responsible for performing a particular function. The functions may be programmable or non-programmable. The integrated circuits also have communication buffer logic to communicate with other integrated circuits. The buffer logic minimally includes transmitter logic to transmit outgoing communication signals (e.g., output signals based on a core logic output signal) and/or receiver logic to receive incoming communication signals (e.g., input signals to core logic from another source such as another integrated circuit). This architecture is necessary because the core logic is generally powered using a small voltage source (also known as “a voltage supply” or as “a voltage rail”) while communication signals between integrated circuits generally require logic one values that are larger than the voltage source of the core logic. For example, core logic of an integrated circuit may be powered by a 1.2 V or 1.8 V voltage source while communication signals may have a logic one value of 3.3 or 5.0 V. Accordingly, it is known to use a separate voltage source for the communication buffer logic. The use of one or more power sources in an integrated circuit results in different power domains or voltage islands within the integrated circuit.
This architecture is generally applicable to a wide variety of integrated circuits. For example, processor IC's, memory IC's, chip set IC's and ASIC's all incorporate the core logic/communication buffer logic scheme described above. A processor IC may include any suitable processing integrated circuit or integrated circuit package such as, but not limited to, a central processing unit, a graphics processing unit, processing cores within a processor, processing engines, accelerators, etc. A memory IC may include any integrated circuit or integrated circuit package capable of storing data whether volatile or non-volatile such as, for example, a DRAM. A chip set IC may include any suitable bridge integrated circuit or bridge integrated circuit package such as, but not limited to a northbridge, a southbridge and a combined northbridge+southbridge.
It is further known that electronic devices are consistently being driven to operate faster and consume less power. One way to meet these demands is to supply integrated circuits with faster clocks and smaller voltage supply levels while reducing the gate thickness of individual transistors on integrated circuits. Accordingly a variety of different types of transistors have been developed to meet this demand. For example, a first type of transistors (“1X transistors”) is characterized by supporting a 1.8 V power supply and generating a 1.8 V logic one value. 1X transistors are further characterized by being designed based on, among other things, a reliability criterion that indicates how reliable the transistor will be over a period of time when exposed to a variety of voltage differences between any two terminals of the transistor. As used herein, transistors have three terminals: a gate, a first terminal and a second terminal. 1X transistors presently have a reliability criterion indicating that they will provide 10 years of reliable operation if exposed to no more than 1.8 V plus a predetermined tolerance voltage between any two terminals. The predetermined tolerance value may be any suitable percentage or voltage amount. It is not uncommon to see tolerance values expressed as 20%.
Those having ordinary skill in the art will recognize that other types of transistors may exist. For example, transistors supporting a 3.3 V power supply and generating a 3.3 V logic one value are referred to as 2X transistors. 2X transistors presently have a reliability criterion indicating that they will provide 10 years of reliable operation if exposed to no more than 3.3 V plus a predetermined tolerance voltage between any two terminals. The predetermined tolerance value may be the same as that described above with respect to 1X transistors. Similarly, transistors supporting a 5.0 V power supply and generating a 5.0 V logic one value are referred to as 3X transistors. 3X transistors presently have a reliability criterion indicating that they will provide 10 years of reliable operation if exposed to no more than 5.0 V plus a predetermined tolerance voltage between any two terminals. The predetermined tolerance value may be the same as that described above with respect to 1X transistors.
Although 1X, 2X and 3X transistors were described above with reference to 1.8 V, 3.3 V and 5.0 V respectively, it is understood that 1X, 2X and 3X transistors may be described with reference to another suitable voltage level. For example, a 1X transistor may refer to a transistor that supports a 1.2 V power supply and that generates a 1.2 V logic one value with a similar 10 year reliability criterion if exposed to no more than 1.2 V plus a predetermined tolerance range of approximately 20% between any two terminals.
Because certain transistors can only withstand a predetermined amount of voltage difference between any two terminals, engineers and circuit designers have often used more than one voltage source to supply power to an integrated circuit or to a given power domain or voltage island within an integrated circuit. A prior art example is illustrated in the schematic circuit diagram of an integrated circuit 100 of FIG. 1. More specifically, the integrated circuit 100 of FIG. 1 illustrates one example of prior art communication buffer logic 102. Communication buffer logic 102 is illustrated as including: transmitter logic 104 and pre-buffer logic 106 where the transmitter logic 104 is capable of generating an outgoing communication signal 128. Although not illustrated, one having ordinary skill in the art will recognize that communication buffer logic 102 may include receiver logic that is capable of receiving incoming communication signals from any other suitable source (e.g., from another integrated circuit). In other embodiments, pre-buffer logic 106 (or just voltage range translation logic 112) may be part of the core logic (not illustrated). The pre-buffer logic 106 and the transmitter logic 104 are illustrated as being coupled to two voltage sources: a first voltage source (VDD_1) 108 operating at, for example, 3.3. V and a second voltage source (VDD_2) 110 operating at, for example, 1.8 V. It is understood that other voltage sources may supply power to the remainder of the integrated circuit. For example, core logic may have a third voltage source operating at, for example, 1.2 V.
Pre-buffer logic 106 includes voltage range translator logic 112, a first inverter circuit I1 and a second inverter circuit I2. The voltage range translator logic 112 is coupled to receive at least one core logic output signal 118 from the core logic. The at least one core logic output signal 118 may have a logic one value at any suitable voltage level (e.g., 1.2 V). In one embodiment, the at least one core logic output signal 118 has a logic one value such that the voltage range translator logic 112 may be implemented using 1X transistors. Core logic may be any suitable logic capable of issuing at least one core logic output signal 118 for controlling the output of the transmitter logic 104. As is known, the at least one core logic output signal 118 may include control information and/or transmission information. The control information may enable or disable the transmitter logic 104 and/or receiver logic (not shown). For example, the transmitter logic 104 may be disabled when receiver logic is receiving incoming communication signals. The transmission information may be transmitted in the outgoing communication signal 128 by the transmitter logic 104.
Based on the at least one core logic output signal 118, the voltage range translator logic 112 generates a first translated signal 120 and a second translated signal 122. The first translated signal 120 is input to the first inverter circuit I1 having the first voltage source 108 as its high power supply and having the second voltage source 110 as its low power supply. The second translated signal 122 is input to the second inverter circuit I2 having the second voltage source 110 as its high power supply and having the ground as its low power supply. The first translated signal 120 is characterized as having a voltage range of VDD_2 to VDD_1. That is, a logic zero is represented by a voltage level of VDD_2 while a logic one is represented by a voltage level of VDD_1. The second translated signal 122 is characterized as having a voltage range of 0 V to VDD_2. That is, a logic zero is represented by a zero voltage while a logic one is represented by a voltage level of VDD_2. Accordingly, both of the first and second inverter circuits I1 and I2 may be implemented using 1X transistors.
When the at least one core logic output signal 118 contains transmission information for communication in the outgoing communication signals 128, the first and second translated signals 120 and 122 mirror, match or otherwise mimic the logic states of the transmission information in the at least one core logic output signal 118. However, when the at least one core logic output signal 118 contains control information indicating that transistor logic 104 should be disabled, the first and second translated signals 120 and 122 may take any suitable form to suitable control (and disable) the transmitter logic 104. In the event that the communication buffer logic 106 includes receiver logic (not shown), the pre-buffer logic may supply the first and second pre-buffer logic output control signals 124 and 126 to the receiver logic to enable or disable it based on the control information in the at least one core logic output control signal 118.
The first inverter circuit I1 generates a first pre-buffer logic output control signal 124 based on the first translated signal 120. Similarly, the second inverter circuit I2 generates a second pre-buffer logic output control signal 126 based on the second translated signal 122. Each inverter circuit I1 and I2 performs the logical inversion function to its input in generating the above corresponding outputs, the first and second pre-buffer logic output control signals 124 and 126. The first and second pre-buffer logic output control signals 124 and 126 are used to suitably drive transmitter logic 104 based on the information present in the at least one core logic output signal 118. In this manner, the first and second pre-buffer logic output control signal are a massaged form (that is, a translated form) of the at least one core logic output signal 118.
Transmitter logic 104 is coupled to the pre-buffer logic 106 and receives the first pre-buffer logic output signal 124 and the second pre-buffer logic 126. Transmitter logic 104 includes a plurality of 1X transistors. As used herein, transistors have two terminals and a gate, wherein the gate may be termed a third terminal. Transistors may be implemented in any suitable technology such as MOSFET technology. Transmitter logic 104 includes first pmos transistor P1, second pmos transistor P2, first nmos transistor N1 and second nmos transistor N2 coupled in a cascaded fashion: the first terminal of P1 is coupled to the first voltage source 108; the gate of P1 is coupled to receive the first pre-buffer logic output control signal 124; the second terminal of P1 is coupled to the first terminal of P2; the gate of P2 is coupled to the second voltage source 110 and to the gate of N1; the second terminal of P2 is coupled to the first terminal of N1; the second terminal of N1 is coupled to the first terminal of N2; the gate of N2 is coupled to the second pre-buffer logic output control signal 126; the second terminal of N2 is coupled to the ground. The output of transmitter logic 104, termed outgoing communication signals 128, is the voltage signal seen at the second terminal of P2 and the first terminal of N1. The first and second pre-buffer logic output control signals 124 and 126 control the transmitter logic 104 by controlling the gates of P1, P2, N1 and N2. Accordingly, when the core logic wishes to communicate information to, for example, another integrated circuit, the outgoing communication signal 128 matches the logic states of the transmission information associated with the at least one core logic output signal 118 but is at a higher voltage level. In this embodiment, the outgoing communication logic 128 has a logic one value of VDD_1 (i.e., 3.3 V).
FIG. 2 illustrates a block diagram of integrated circuit 200 similar to that of integrated circuit 100 of FIG. 1 with at least one core logic 202 and two different communication buffer logic rings: communication buffer logic ring_0 with power domain_0 204 and communication buffer logic ring_1 with power domain_1 206. Power domain_0 is associated with one voltage source (e.g., 3.3 V) while power domain_1 is associated with another voltage source (e.g., 5.0 V). The at least one core logic 202 may be associated with one or more corresponding voltage sources and may send core logic output signals to one or more communication buffer logic units 102. In this embodiment, the term “unit” is merely used to differentiate between each communication buffer logic 102. Each of the communication buffer logic rings 204 and 206 includes a plurality of communication buffer logic units 102 as illustrated in FIG. 1. Because each communication buffer logic unit 102 may communicate with one or more other integrated circuits, integrated circuit 200 is a versatile component of a electronic system requiring communication among a plurality of integrated circuits that require communication signals at either the voltage level associated with power domain_0 or the voltage level associated with power domain_1.
It is known that power domains can be characterized as having three operational modes. During a normal operation mode, all power supplies have sufficiently ramped up from 0 V to the voltage level at which they are designed to supply power. During ramp up operation mode, the power supplies are increased from 0 V to the voltage level at which they are designed to supply power. Conversely, during ramp down operation mode, the power supplies are decreased from the voltage level at which they are designed to supply power to 0 V.
Turning back to the prior art integrated circuit 100, during normal operation, the communication buffer logic 102 properly and accurately operates to deliver the correct outgoing communication signals 128 (and to receive and communicate to the core logic the correct incoming communication signals by way of the receiver logic, not shown). However, during ramp up operation mode and during ramp down operation mode, the voltage levels of the first voltage source 108 and the second voltage source 110 may cause the communication buffer logic 102 to act improperly and/or inaccurately thereby resulting in improper outgoing communication signals 128. The ramping voltage levels similarly and adversely affect the integrity of information contained within the incoming communication signals received by the receiver logic, not shown. This is complicated further because each of the voltage sources for the communication buffer logic 102 (and/or for the remainder of the integrated circuit 100, such as for example core logic) may be independently ramping up or down.
As a result of this sporadic, improper and inaccurate behavior of the communication buffer logic 102, the outgoing communication signals 128 transmitted by transmitter logic 104 may be improper and cause glitches or domino-effect errors for other integrated circuits that receive and rely on information contained therein. Although not specifically shown, if the communication buffer logic 102 includes receiving logic, the voltage ramping up and/or down of the first and second voltage sources 108 and 100 may further cause the core logic to receive inaccurate core logic input signals sent from other integrated circuits.
One prior art solution to the above referenced improper and inaccurate behavior of communication buffer logic 102 includes the use of external switches (e.g., weak pull-up transistors if there is a need to provide a logic one to another integrated circuit or weak pull down transistors if there is a need to provide a logic zero to another integrated circuit) that were placed alongside the trace or metal of a printed circuit board (PCB) communicating the outgoing communication signals 128 to another integrated circuit. The external switches are not only expensive, but cause additional signal integrity issues due to the difficulties of matching the impedance of the switch to the impedance of the trace. Because it is nearly impossible to properly match the impedance of the switch to that of the trace, the communication signal integrity was degraded due to reflection of the signals.
Accordingly, a need exists to correct the behavior of integrated circuits and specifically the communication buffer logic portions of integrated circuit during ramping periods such that communication signals may not cause other errors throughout the remainder of a system. A need further exists to provide such a solution while avoiding the use of external switches that cause further signal degradation. | {
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Many computing systems include at least one display and at least one input device. The display may include, for example, a monitor, a screen, or the like. Example input devices include a mouse, a keyboard, a touchpad, or the like. Some computing systems include a touch-sensitive display to both display output of the computing system and receive physical (e.g., touch) input. | {
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This invention relates to processes for the preparation of cyanoalkylphenols.
Cyanoalkylphenols have numerous applications and are particularly useful as chemical intermediates in the preparation of polyurethanes, epoxy resins and pharmaceutical and agricultural products.
Methods are known for preparing cyanoalkylphenols. One process for the preparation of cyanoalkylphenols involves a complex multi-step synthesis whereby a dimethylbenzylhalide is converted to the cyanide, ring nitrated, hydrogenated, and then subjected to diazotization. See A. Johnsson, Act. Chem. Scand 8, 1203-10 (1954). The problem with this process is that it is a low-yielding, multi-step, time-consuming, and uneconomical route.
Another process for the preparation of cyanoalkylphenols is disclosed in U.S. Pat. No. 4,405,528. This is a process for the synthesis of 4-(.alpha.-alkyl-.alpha.-cyanomethyl)-2,6-disubstituted phenol by reacting a 2,6-disubstituted phenol with a Friedel-Crafts addition agent in the presence of a Friedel-Crafts catalyst such as aluminum chloride to form the corresponding 4-(.alpha.-alkyl-.alpha.-oxomethyl)-2,6-disubstituted phenol, reducing the 4-(.alpha.-alkyl-.alpha.-oxomethyl)-2,6-disubstituted phenol to form the corresponding 4-(.alpha.-alkyl-.alpha.-hydroxymethyl)-2,6-disubstituted phenol and thereafter reacting the 4-(.alpha.-alkyl-.alpha.-hydroxymethyl)-2,6-disubstituted phenol with an alkali metal cyanide or an alkaline earth metal cyanide to form the desired 4-(.alpha.-alkyl-.alpha.-cyanomethyl)-2,6-disubstituted phenol.
A process for the preparation of 4-(.alpha.-hydrocarbyl-.alpha.-cyanomethyl)-2,6-disubstituted phenols is disclosed in U.S. Pat. No. 4,483,800 wherein said cyanomethylphenol is prepared by reacting a disubstituted phenol with an aldehyde and an alkali metal cyanide or an alkaline earth metal cyanide in a suitable solvent.
What is needed is a versatile one-step process for utilizing inexpensive, readily available starting materials to produce cyanoalkylphenols. | {
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The present invention relates to fixing devices and, more particularly, to a fixing device used for mounting a storage device.
Storage devices such as a hard disk drive (HDD), which are auxiliary memory device for computers, reproduce information stored in a magnetic disk or record new information on the magnetic disk by way of a magnetic head. A rotating speed of the hard disk requires to be higher and higher. However, when the hard disk drive is fixed on a support bracket without any buffer for protection or is assembled in an improper way, the hard disk drive is prone to generate vibration once the hard disk drive works. If the hard disk drive vibrates for a long time, the magnetic head of the hard disk drive may be damaged or a magnetic track of the magnetic disk may be scraped. As a result, information stored in the hard disk drive may be lost. Additionally, a noise generated by the hard disk drive would disturb a user at night. | {
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Modern wireless and wireline communications systems provide various types of services to customers, including normal calling, paging, messaging, internet access, etc., where the customer (sometimes referred to as a subscriber) is able to select from a wide range of calling plans for today's mobile phone. Most plans are either post-paid, in which services are provided in a given time period, with the customer being billed at the end of the billing period, or pre-paid type plans in which the customer must pay in advance to ensure communications services are available when subsequently needed. Service providers currently offer a number of calling plans designed to allow subscribers to select the types of services that will be available when using their mobile phone or phones. Most post-paid service plans offer either limited anytime minute plans, for instance, in which the subscriber may use 300, 500, 700, 1,000 minutes at a favorable price within a given billing period, typically a month, as well as unlimited plans. For post-paid plans offering limited anytime minutes, the subscriber can use up to the stated limit at a first rate (often included in a flat rate monthly base charge), after which further minutes are charged at a higher rate, with the bill reflecting any charges for exceeding the minutes limit. For pre-paid plans, the user can make calls until the account balance reaches zero, after which the phone will not work until the subscriber replenishes the account.
Shared subscriber plans or family plans are becoming popular, in which post-paid services are provided for a number of phones, with the costs being billed together. Such plans are typically directed to family groups, friends, small businesses, etc., where the plan holder is allowed to have multiple phones with multiple phone numbers. As with single subscriber plans, the shared subscriber plans may also be provided with unlimited minutes or with a limited number of total anytime minutes for the group as a whole, with overages being reflected on the bill at the end of the month. In many group situations, however, one or a few shared plan members use the majority of the available minutes, with the plan account often incurring excess charges with no control over the overall group usage and no indication of excessive phone use by certain members until the bill is received. | {
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Internet Protocol (IP) multicast enables modern data networks to save bandwidth and processing capacity by reducing the number of copies of data packets transmitted from a source to a destination. In a traditional unicast model, source devices transmit content (e.g., a video file, etc.) directly to a destination device by referencing an IP address associated with the destination device. Therefore, even if multiple destination devices are requesting the same content at the same time, multiple copies of the content are transmitted simultaneously. While this model is effective for on-demand content-related activity, such as web browsing, it is inefficient for some types of media distributions, such as streaming video for IP television, distance learning, etc.
Multicast operates in a manner more similar to a traditional broadcast model. Destination devices wishing to receive content from a particular source join a multicast group designated by a particular address. The content is delivered to all destinations associated with the address. Because they share a common address, known as the multicast group address, only a single copy of the content needs to be transmitted across any single hop in a network, such as between routers, etc.
Unfortunately, implementing IP multicast (IP being a layer 3 protocol) on a layer 2 network, such as the ATM network which forms the basis of many broadband passive optical networks (BPONs), typically requires significant overhead, thereby reducing its effectiveness. | {
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Simple helical antennas appear to have been investigated thoroughly by many persons skilled in the antenna art and are currently used in many different applications. The helical antenna represents a transition between linear-element antennas and loop antennas.
The Antenna Handbook, edited by Y. T. Lo and S. W. Lee, Van Nostrand Reinhold Company, New York, N.Y., 1988, describes helical circularly polarized antennas in FIG. 6 at page 3-31, pages 27-15 through 27-17 and in FIGS. 14 through 19. Single helices and multiple (bifilar) helices for single antennas are illustrated.
A detailed presentation of the basic concepts and analysis of the helical antenna is supplied in Antennas, Second Edition, by J. D. Kraus, McGraw-Hill, New York, N.Y., 1988, in Chapter 7. Satellite-borne arrays of side-by-side helices are shown. Kraus also depicts a number of antenna configurations including a driven helix having a parasitic helix of about the same diameter wound over it for producing increased gain. He also describes end-to-end helices.
In The Antenna Engineering Handbook, R. C. Johnson, Editor, Third Edition, McGraw-Hill, New York, N.Y., 1993, Chapter 13, King et al. present a detailed description of the performance of helical antennas. King et al. describe single or multiple conductors wound into a helical shape. They describe the axial, normal and higher order modes of operation. Helices with uniform diameter, non-uniform diameter and tapering diameters are discussed. The latter types of helices exhibit greater broad-band frequency response and better circular polarization over a wide band than does the helix with uniform diameter. King et al. discuss short axial mode helices as single antenna elements and in side-by-side arrays. They describe helical windings of circular wire and of ribbon-like flat windings on dielectric material.
As discussed by Kraus and King et al., the helical antenna has different modes of energy propagation which are controlled by its geometry. The most common are axial mode and normal mode. Axial mode, used most widely, provides maximum radiation along the helix axis. This mode occurs when the helix circumference is of the order of one wavelength of the propagated energy. The normal mode occurs when the helix diameter is small with respect to one wavelength and yields radiation generally directed broadside, that is, 90 degrees from the helix axis. Such helices are commonly used in flexible antennas for hand held transceivers and provide shorter antennas.
When a satellite communicates with Earth stations in very high frequency (VHF) and ultra high frequency (UHF) bands, two different helices having different geometry are generally required. One helix operates at VHF and the other smaller helix operates at UHF. The two helices are usually mounted separately, either linearly end-to-end, or side-by-side. However, there are disadvantages to each of these methods of mounting.
End-to-end mounting produces a very long antenna which requires a large stowage space or folding the antenna. Deployment on orbit becomes more difficult when the antenna is folded for stowage. Side-by-side mounting often results in asymmetric coverage by the two radiated beams. If an array of helical elements is needed for increased gain, this configuration can become too unwieldy to stow and deploy because of the volume it occupies.
It would be a significant commercial advantage for a multi-band antenna to be constructed with the higher frequency helix mounted concentrically within the lower frequency helix. Such a system would offer a much more compact antenna than those currently available. For example, as a result of the reduced length, the antenna could be compressed, "spring-like," for stowage aboard a launch vehicle and easily deployed to fill length on orbit by releasing the restraint on the "spring." Moreover, the helical elements could be sized to produce radiation in a novel conical mode which produces a radiation pattern with significant advantages for satellite-to-Earth station communications.
The inventors believe that persons skilled in the antenna arts have worked with designs that generally teach away from concentric helices. Others have proposed to use concentric helices with different polarization at the same frequency for uplink and downlink. A right hand helix might be used for uplink and a left hand helix for downlink. It is the inventors' understanding that this method proved unsuccessful in simulations.
Originally the inventors believed that mutual electric field coupling between concentric helices was much smaller than generally thought and pursued concentric helices operating at different frequencies. Successful designs were subsequently discovered when the frequency difference between concentric helices was at least two to one.
The development of a multi-band concentric helical antenna would constitute a major technological advance and would satisfy a long felt need in the satellite and telecommunications industries. | {
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The present invention relates to a method of operating electrolytic reduction cells for the production of aluminum.
In the Hall-Heroult process aluminum is produced by the passage of electric current through a molten electrolyte consisting of cryolite (Na.sub.3 AlF.sub.6) with normally an excess of AlF.sub.3 and small quantities of other alkali metal and alkaline earth metal fluorides such as LiF, CaF.sub.2 and MgF.sub.2 and containing dissolved alumina in an amount of about 2-8%. The cell is lined with carbon blocks which form the cathode and one or more carbon anodes are suspended above the cell and dip into the electrolyte.
The anodes may be of the pre-baked block type or the Soderberg type, in which a viscous carbonaceous mix is fed into a casing and is baked in situ.
In normal operation current passing between the anode and cathode decomposes alumina to form aluminium, which collects at the cathode, and oxygen, which is released at the anode and combines with the carbon anode to form gaseous oxides, which are freely ejected from under the anode face, because the carbon oxides do not wet the anode material.
In operating the electrolytic reduction cell the molten electrolyte is covered with a crust of solid material, onto which fresh alumina is supplied. Fresh alumina is supplied to the cell by breaking the crust and it is therefore not always possible to correctly gauge the amount of alumina that enters the electrolyte at each crust-breaking operation. In consequence occasionally the concentration of alumina in the cell electrolyte falls to a novel (0.5-2.2% alumina) where the fluoride salts start to decompose with consequent formation of gaseous fluorine compounds. These consist primarily of carbon tetrafluoride, which, unlike the carbon oxides, wet the anode material to form a stubborn, high-resistance film on the anode face and severely reduce the contact area between the face of the carbon anode and electrolyte. Under this condition, the overall cell voltage typically rises from 5 to 40 volts.
This phenomenon is normally referred to as "an anode effect". It is well known that corrective action must be taken quickly to counteract the deleterious results of the "anode effect" and regain normal operation of the cell. It is conventional to commence corrective action as soon as the cell voltage rises above 10 volts. In addition to restoring the alumina content to a normal operating level of 2-8%, positive action is required to remove the high resistance gas film at the anode face so as to reduce electrical resistance at the anode/electrolyte interface and to restore the current density at the interface to the normal operating level in the region of 0.55-1.10 amps/cm.sup.2.
In conventional practice when an anode effect is detected as a result of a sudden large rise in the cell operating voltage, the alumina concentration of the bath is restored by breaking the crust, and this is immediately followed by action to remove the layer of gaseous fluoride on the bottom face(s) of the anode(s) and to reduce the current density on the major portion thereof. For example, it is known to remove the gaseous film by scraping the anode face with a steel rake, by rapid injection of air into the inter-electrode space or by the insertion of a wooden pole under the anode. The last method depends on the rapid decomposition of the wood in contact with the bath electrolyte (circa 1000.degree. C.) with consequent release of large quantities of gas to flush the anode face. At the same time sufficient local disturbance in the metal pool is created to cause short circuiting of the metal to the anode face. This reduces the current density on the remainder of the anode face. Once the current density falls below a given critical value, the process is restarted.
The conventional methods of clearing "anode effects" are labour intensive and have other disadvantages. A significant quantity of materials, such as steel rakes or wooden poles is consumed with consequent introduction of impurities into the cell, and reoxidation of metal. Moreover these methods are virtually incapable of being performed under automatic control in response to rise in cell voltage.
Various methods of clearing anode effects, involving physical vertical movement of the anodes, have been devised. All electrolytic reduction cells are equipped with jacks for vertical movement of the anodes which are required to maintain the anode-cathode distance as nearly as possible at a target value, chosen to provide optimum cell operation. The consumption of anode material and the increase in the depth of the metal pool (the surface of which is the effective cathode surface) require periodic change in the anode face position to re-adjust the anode-cathode distance to the target value. Thus the cells are equipped with power-driven means for anode movement.
Existing methods of clearing anode effects by vertical movement of the anode involve some crust breaking action and increase of the alumina content of the bath. These methods have involved lowering the anode to bring the anode face into contact with the metal pool. The contact between the anode and the metal pool has the effect of displacing the fluoride gas film and at the same time short circuits the bath, thus reducing the current density on the remaining major portion of the anode face, which is out of contact with the molten metal. It is known that when the alumina content of the bath has been restored to a correct level and the process has been restarted by creating a local displacement of the fluoride gas film on the anode face and a local short circuit of the bath, the generated carbon oxides will flush away the remainder of the fluoride gas on the anode surface. This restores the cell to its normal operating condition.
Clearance of anode effects by anode lowering has been reasonably successful with electrolytic reduction cells of both the prebake-anode and horizontal-stud Soderberg type. In addition to reduction of current density on large areas of anode face, the method relies on replenishing and mixing alumina in the electrolyte bath through the tidal movement of the electrolyte in the peripheral region between the anode(s) and the cell wall resulting from the displacement of electrolyte as the anode(s) are first lowered and then raised.
That method of clearing anode effects can be initiated automatically in response to increase in cell voltage. Because of the high ratio of anode face area to bath surface area in the annulus between anode and cell side wall in a vertical stud Soderberg type cell, upward displacement of bath resulting from the lowering of the anode to make a short circuit would result in unacceptably large and frequent spillage of molten electrolyte. Furthermore the resulting movement of the electrolyte can lead to blockage of the gas collection skirt on the anode by frozen electrolyte. | {
"pile_set_name": "USPTO Backgrounds"
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Assays capable of detecting the presence of a particular nucleic acid molecule in a sample are of substantial importance in forensics, medicine, epidemiology and public health, and in the prediction and diagnosis of disease. Such assays can be used, for example, to identify the causal agent of an infectious disease, to predict the likelihood that an individual will suffer from a genetic disease, to determine the purity of drinking water or milk, or to identify tissue samples. The desire to increase the utility and applicability of such assays is often frustrated by assay sensitivity. Hence, it would be highly desirable to develop more sensitive detection assays.
The usefulness of a detection assay is often limited by the concentration at which a particular target nucleic acid molecule is present in a sample. Thus, methods that are capable of amplifying the concentration of a nucleic acid molecule have been developed as adjuncts to detection assays.
One method for overcoming the sensitivity limitation of nucleic acid concentration is to selectively amplify the nucleic acid molecule whose detection is desired prior to performing the assay. Recombinant DNA methodologies capable of amplifying purified nucleic acid fragments in vivo have long been recognized. Typically, such methodologies involve the introduction of the nucleic acid fragment into a DNA or RNA vector, the clonal amplification of the vector, and the recovery of the amplified nucleic acid fragment. Examples of such methodologies are provided by Cohen et al. (U.S. Pat. No. 4,237,224), Maniatis, T. et al., Molecular Cloning (A Laboratory Manual), Cold Spring Harbor Laboratory, 1982, etc.
In many instances in clinical medicine and diagnostics, however, the concentration of a target species in a sample under evaluation is so low that it cannot be readily cloned. To address such situations, methods of in vitro nucleic acid amplification have been developed that employ template directed extension. In such methods, the nucleic acid molecule is used as a template for extension of a nucleic acid primer in a reaction catalyzed by polymerase.
One such template extension method is the "polymerase chain reaction" ("PCR"), which is among the most widely used methods of DNAn amplification (Mullis, K. et al., Cold Spring Harbor Symp. Quant. Biol. 51:263-273 (1986); Erlich H. et al., EP 50,424; EP 84,796, EP 258,017, EP 237,362; Mullis, K., EP 201,184; Mullis K. et al., U.S. Pat. No. 4,683,202; Erlich, H., U.S. Pat. No. 4,582,788; Saiki, R. et al., U.S. Pat. No. 4,683,194 and Higuchi, R. "PCR Technology," Ehrlich, H. (ed.), Stockton Press, NY, 1989, pp 61-68), which references are incorporated herein by reference).
The polymerase chain reaction can be used to selectively increase the concentration of a nucleic acid molecule even when that molecule has not been previously purified and is present only in a single copy in a particular sample. The method can be used to amplify either single- or double-stranded DNA. The essence of the method involves the use of two oligonucleotides to serve as primers for the template-dependent, polymerase mediated replication of the desired nucleic acid molecule.
The precise nature of the two oligonucleotide primers of the PCR method is critical to the success of the method. As is well known, a molecule of DNA or RNA possesses directionality, which is conferred through the 5'.fwdarw.3' linkage of the sugar-phosphate backbone of the molecule. Two DNA or RNA molecules may be linked together through the formation of a phosphodiester bond between the terminal 5' phosphate group of one molecule and the terminal 3' hydroxyl group of the second molecule. Polymerase dependent amplification of a nucleic acid molecule proceeds by the addition of a nucleotide having 5' phosphate to the 3' hydroxyl end of a nucleic acid molecule. Thus, the action of a polymerase extends the 3' end of a nucleic acid molecule. These inherent properties are exploited in the selection of the two oligonucleotide primers of the PCR. The oligonucleotide sequences of the two primers of the PCR method are selected such that they contain sequences identical to, or complementary to, sequences which flank the sequence of the particular nucleic acid molecule whose amplification is desired. More specifically, the nucleotide sequence of the Amplification Primer is selected such that it is capable of hybridizing to an oligonucleotide sequence located 3' to the sequence of the desired nucleic acid molecule that is to be amplified, whereas the nucleotide sequence of the Target Primer is selected such that it contains a nucleotide sequence identical to one present 5' to the sequence of the desired nucleic acid molecule that is to be amplified. Both primers possess the 3' hydroxyl groups which are necessary for enzyme mediated nucleic acid synthesis.
In the polymerase chain reaction, the reaction conditions must be cycled between those conducive to hybridization and nucleic acid polymerization, and those which result in the denaturation of duplex molecules. In the first step of the reaction, the nucleic acid molecules of the sample are transiently heated, and then cooled, in order to denature any double stranded molecules that may be present. The amplification and Target Primers are then added to the sample at a concentration which greatly exceeds that of the desired nucleic acid molecule. When the sample is then incubated under conditions conducive to hybridization and polymerization, the Amplification Primer will hybridize to the nucleic acid molecule of the sample at a position 3' to the sequence of the desired molecule to be amplified. If the nucleic acid molecule of the sample was initially double stranded, the Target Primer will hybridize to the complementary strand of the nucleic acid molecule at a position 3' to the sequence of the desired molecule that is the complement of the sequence whose amplification is desired. Upon addition of a polymerase, the 3' ends of the amplification and (if the nucleic acid molecule was double stranded) Target Primers will be extended. The extension of the Amplification Primer will result in the synthesis of a DNA molecule having the exact sequence of the complement of the desired nucleic acid. Extension of the Target Primer will result in the synthesis of a DNA molecule having the exact sequence of the desired nucleic acid.
The PCR reaction is capable of exponentially amplifying the desired nucleic acid sequences, with a near doubling of the number of molecules having the desired sequence in each cycle. This exponential increase occurs because the extension product of the Amplification Primer contains a sequence which is complementary to a sequence of the Target Primer, and thus can serve as a template for the production of an extension product of the Target Primer. Similarly, the extension product of the Target Primer, of necessity, contain a sequence which is complementary to a sequence of the Amplification Primer, and thus can serve as a template for the production of an extension product of the Amplification Primer. Thus, by permitting cycles of hybridization, polymerization, and denaturation, an exponential increase in the concentration of the desired nucleic acid molecule can be achieved. Reviews of the polymerase chain reaction are provided by Mullis, K. B. (Cold Spring Harbor Symp. Quant. Biol. 51:263-273 (1986)); Saiki, R. K., et al. (Bio/Technology 3:1008-1012 (1985)); and Mullis, K. B., et al. (Met. Enzymol. 155:335-350 (1987), which references are incorporated herein by reference).
PCR technology is useful in that it can achieve the rapid and extensive amplification of a polynucleotide molecule. However, the method has several salient deficiencies. First, it requires the preparation of two different primers which hybridize to two oligonucleotide sequences of the target sequence flanking the region that is to be amplified. The concentration of the two primers can be rate limiting for the reaction. Although it is not essential that the concentration of the two primers be identical, a disparity between the concentrations of the two primers can greatly reduce the overall yield of the reaction.
A further disadvantage of the PCR reaction is that when two different primers are used, the reaction conditions chosen must be such that both primers "prime" with similar efficiency. Since the two primers necessarily have different sequences, this requirement can constrain the choice of primers and require considerable experimentation. Furthermore, if one tries to amplify two different sequences simultaneously using PCR (i.e. using two sets of two primers), the reaction conditions must be optimized for four different primers.
A further disadvantage of PCR is that it requires the thermocycling of the molecules being amplified. Since this thermocycling requirement denatures conventional polymerases, it thus requires the addition of new polymerase at the commencement of each cycle. The requirement for additional polymerase increases the expense of the reaction, and can be avoided only through the use of thermostable polymerases, such as Taq polymerase. Moreover, the thermocycling requirement attenuates the overall rate of amplification because further extension of a primer ceases when the sample is heated to denature double-stranded nucleic acid molecules. Thus, to the extent that the extension of any primer molecule has not been completed prior to the next heating step of the cycle, the rate of amplification is impaired.
Other known nucleic acid amplification procedures include transcription-based amplification systems (Kwoh D. et al., Proc. Natl. Acad. Sci. (U.S.A.) 86:1173 (1989); Gingeras T. R. et al., PCT appl. WO 88/10315 (priority: U.S. patent applications Ser. Nos. 064,141 and 202,978); Davey, C. et al., European Patent Application Publication no. 329,822; Miller, H. I. et al., PCT appl. WO 89/06700 (priority: U.S. patent application Ser. No. 146,462, filed Jan. 21, 1988)), and "race" (Frohman, M. A., In: PCR Protocols: A Guide to Methods and Applications, Academic Press, NY (1990)) and "one-sided PCR" (Ohara, O. et al., Proc. Natl. Acad. Sci. (U.S.A.) 86:5673-5677 (1989)).
Methods based on ligation of two (or more) oligonucleotides in the presence of nucleic acid having the sequence of the resulting "di-oligonucleotide", thereby amplifying the di-oligonucleotide, are also known (Wu, D. Y. et al., Genomics 4:560 (1989)).
An isothermal amplification method has been described in which a restriction endonuclease is used to achieve the amplification of target molecules that contain nucleotide 5'-[a-thio]triphosphates in one strand of a restriction site (Walker, G. T. et al., Proc. Natl. Acad. Sci. (U.S.A.) 89:392-396 (1992)).
All of the above amplification procedures depend on the principle that an end-product of a cycle is functionally identical to a starting material. Thus, by repeating cycles, the nucleic acid is amplified exponentially.
Methods that use thermocycling, e.g. PCR or Wu, D. Y. et al., Genomics 4:560 (1989)), have a theoretical maximum increase of product of 2-fold per cycle, because in each cycle a single product is made from each template. In practice, the increase is always lower than 2-fold. Further slowing the amplification is the time spent in changing the temperature. Also adding delay is the need to allow enough time in a cycle for all molecules to have finished a step. Molecules that finish a step quickly must "wait" for their slower counterparts to finish before proceeding to the next step in the cycle; to shorten the cycle time would lead to skipping of one cycle by the "slower" molecules, leading to a lower exponent of amplification. | {
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Electronics, microelectronics and microelectromechanics require as starting materials semiconductor wafers with extreme requirements made of global and local flatness, single-side-referenced flatness (nanotopology), roughness and cleanness. Semiconductor wafers are wafers composed of semiconductor materials such as elemental semiconductors (silicon, germanium), compound semiconductors (for example composed of an element of the third main group of the periodic table such as aluminum, gallium or indium and an element of the fifth main group of the periodic table such as nitrogen, phosphorus or arsenic) or the compounds thereof (for example Si1-xGex, 0<x<1).
In accordance with the prior art, semiconductor wafers are produced by means of a multiplicity of successive process steps which can generally be classified into the following groups: (a) producing a usually monocrystalline semiconductor rod; (b) slicing the rod into individual wafers; (c) mechanical processing; (d) chemical processing; (e) chemomechanical processing; (f) if appropriate additional production of layer structures.
A method designated “planetary pad grinding (PPG)” is known as a particularly advantageous method from the group of mechanical processing steps. The method is described for example in DE102007013058A1, and an apparatus suitable therefor is described for example in DE19937784A1. PPG is a method for the simultaneous double-side grinding of a plurality of semiconductor wafers, wherein each semiconductor wafer lies such that it is freely movable in a cutout in one of a plurality of carriers (guide cages, “insert carriers”) caused to rotate by means of a rolling apparatus and is thereby moved on a cycloidal trajectory. The semiconductor wafers are processed in material-removing fashion between two rotating working disks. Each working disk comprises a working layer containing bonded abrasive.
The working layers are present in the form of structured abrasive pads which are fixed on the working layers adhesively, magnetically, in a positively locking manner (for example hook and loop fastener) or by means of vacuum. Suitable working layers in the form of easily exchangeable abrasive pads designed to be self-adhesive on the rear side are described for example in U.S. Pat. No. 5,958,794. The abrasive used in the abrasive pads is preferably diamond.
A similar method is so-called “flat honing” or “fine grinding”. In this case, a plurality of semiconductor wafers in the arrangement described above for PPG are guided on the characteristic cycloidal paths between two large rotating working disks. Abrasive grain is fixedly bonded into the working disks, such that the material removal is effected by means of grinding. In the case of flat honing, the abrasive grain can be bonded directly into the surface of the working disk or be present in the form of an areal covering of the working disk by means of a multiplicity of individual abrasive bodies, so-called “pellets”, which are mounted onto the working disk (P. Beyer et al., Industrie Diamanten Rundschau IDR 39 (2005) III, page 202).
Over the course of time, in the case of the grinding methods described, the shape of the working layers changes as a result of constant wear, residual grain breaking out from the bonding matrix and fresh grain being uncovered. It is known that the wear proceeds radially non-uniformly across the working disk. Over time, the working layers in this way form a trough-shaped radial profile, such that the resulting shape of the processed semiconductor wafers worsens to an increasing degree over the course of the wear.
Depending on the materials of the grinding tool and of the processed workpieces, moreover, the cutting capacity of the grinding tool can decrease over time. In addition, it is generally necessary for a new grinding tool to be dressed prior to the first use, by means of the bonding matrix being superficially removed and the abrasive grain embedded therein being uncovered.
Therefore, the prior art includes trimming new or used grinding tools. During trimming, suitable trimming tools are moved under pressure and relative to the tools to be trimmed, such that material removal from the working disks or layers takes place. “Trimming” is understood to mean both the reestablishment of the target shape of the grinding tool (“truing”), and the dressing thereof, i.e. the reestablishment of its cutting capacity.
P. Beyer et al., Industrie Diamanten Rundschau IDR 39 (2005) III, page 202 and DE102006032455A1 describe trimming apparatuses comprising trimming rings and an outer toothing which can be inserted into the grinding apparatus like a carrier and can be moved relative to the working disks by the drives of said grinding apparatus.
The trimming rings described in P. Beyer et al., Industrie Diamanten Rundschau IDR 39 (2005) III, page 202 support a working layer having material-removing action, said working layer containing ceramically bonded diamond as abrasive. Said trimming rings are only suitable for dressing the working layers described by P. Beyer et al., which are composed of a multiplicity of sintered (vitreous), metallically bonded or synthetic-resin-bonded abrasive bodies—so-called pellets. Upon the use of the trimming apparatus described therein and of the method specified therein for trimming abrasive pads, however, the specified trimming rings subject the abrasive pad to wear, without attaining an appreciable dressing effect. Moreover, the dressing apparatus specified therein has proved to be unsuitable for producing a defined target shape of the working layer.
“3M™ Trizact™ Diamond Tile 677XA Pad Conditioning Procedure Rev. A”, 3M Technical Application Bulletin, September 2003, specifies a method for the initial dressing (“break-in”) of a working layer containing bonded abrasive, in which thin, circular abrasive films are stuck to steel disks. The steel disks are toothed and roll on inner and outer pin wheels of the grinding apparatus. Material removal from the working layer is achieved by relative movement between steel disk and working disks under pressure and with addition of water. This method is actually suitable for subsequently dressing working layers that have become blunt, or for providing newly applied working layers, on the surface of which abrasive has not yet been exposed and which therefore do not yet exhibit a cutting effect, with initial dressing for providing a first cutting effect. The method is extremely impracticable, however, since the thin abrasive films applied by adhesive bonding are usually worn within a single use, which results in an extremely unstable dressing process with fluctuating dressing results. Moreover, the abrasive films specified proved to be unsuitable for obtaining trimming of the working layer to form a defined target shape—preferably plane-parallel surfaces of the two working layers.
DE102006032455A1 states that the trimming is advantageously effected predominantly using free grain. The trimming rings disclosed therein continually release abrasive as a result of constant wear, said abrasive ultimately providing for the necessary material removal from the working layers. It has been found, however, that targeted dressing and, in particular, targeted production of a defined target shape of the working layers are not possible using trimming rings of this type.
In addition to the abovementioned specific disadvantages of the above methods, the following problems generally occur during trimming in accordance with the prior art:
The trimming leads to a direction dependence of the grinding behavior of the dressed working layers. It has been observed, for example, that some abrasive pads used as a working layer already have a preferred direction in a manner governed by production. The fashioning of a preferred direction also occurs as a result of the use and as a result of the trimming itself. Preferred direction should be understood here to mean that the abrasive pad, with identical pressure, identical rotational speeds and rotational speed ratios (“kinematics”) of the drives, identical shape of the working gap between the working disks and identical cooling lubrication, achieves a higher material removal rate in one direction than in the case of operation with rotational speeds that are in each case exactly the opposite in terms of sign, but identical rotational speed ratios and identical pressure, gap shape and cooling lubrication. The directional dependence of the grinding behavior has the effect that only very limited rotational speed combinations can be used for the drives of the grinding apparatus.
In addition, during operation in only one direction, the thin carriers for the semiconductor wafers only ever roll in one direction and wear non-uniformly and hence more rapidly by comparison with more uniform loading during operation with a changing direction. This reduces the usable life of the expensive carriers and makes the method uneconomic.
The working layer, too, constantly alters its properties during grinding operation only in one direction. Changing operation with directions of rotation of the drives of the grinding apparatus that alternate from pass to pass or at least from pass block to pass block counteracts that and thus permits more uniform operating conditions.
If the working layers have a preferred direction, however, operation with alternating drive directions is not possible since thickness, shape, removal rate and surface roughness of the workpieces would then constantly alternate, constantly changing heat inputs would make extremely stringent requirements of the regulation of a desirably uniform processing process and, moreover, the working layers would be worn differently and would have to be frequently trimmed or dressed, which necessitates additional process interruptions that adversely affect the economic viability of the method.
These restrictions make the otherwise advantageous PPG method and the measures known in the prior art for keeping constant the shape and cutting behavior of the working layers unsuitable for producing semiconductor wafers of high flatness for particularly demanding applications.
When the working layers are used for grinding workpieces such as semiconductor wafers, for example, the upper and the lower working layers can be subjected to wear of differing magnitudes. The known trimming methods are not able to take account of this different wear, for which reason generally more material than necessary is removed from one of the working layers during trimming. This unnecessary material removal has the effect that the working layers have to be changed more frequently than necessary.
The toothed rings or pin wheels of the rolling apparatus of the grinding machine have a small height coordinated with the thickness of the workpieces usually processed, and are also height-adjustable only to a small extent. Consequently, it is not possible to use trimming bodies of any desired thickness which lead to a height of corresponding magnitude for the trimming apparatuses. This has the effect that the trimming apparatuses or at least the trimming bodies have to be frequently changed.
FIG. 5 shows the essential elements of an apparatus according to the prior art whose working layers can be trimmed by means of the methods according to the invention. The illustration shows the basic schematic diagram of a two-disk machine for processing disk-shaped workpieces such as semiconductor wafers, as is disclosed for example in DE19937784A1, in perspective view. An apparatus of this type has an upper working disk 51 and a lower working disk 52 with collinear rotational axes 53 and with substantially plane-parallel arrangement of the working surfaces of the working disks with respect to one another. According to the prior art, the working disks 51 and 52 are fabricated from gray cast iron, cast stainless steel, ceramic, composite materials or the like. The working surfaces are uncoated or provided a coating made of, for example, stainless steel or ceramic, etc. The upper working disk contains numerous holes 54 through which a cooling lubricant (e.g. water) can be fed to the working gap 55. The apparatus is provided with a rolling apparatus for carriers 56. The rolling apparatus consists of an inner drive ring 57 and outer drive ring 58. The carriers 56 each have at least one cutout which can receive a workpiece 59 to be processed, for example a semiconductor wafer. The rolling apparatus can be embodied for example as pin gearing, as involute gearing or as some other customary type of gearing. Upper working disk 51 and lower working disk 52 and inner drive ring 57 and outer drive ring 58 are driven at rotational speeds no, nu, ni and na about substantially identical axes 53. In this case, “substantially” means that the offset of the axes of rotation of the individual drives relative to the central axis of all the drives amount to less than one per mille of the diameter of the working disks, and the tilting of the axes with respect to one another amounts to less than 2°. A cardanic suspension of the upper working disk 51 compensates for any residual tilting of the axes, such that the mutually facing working surfaces of the working disks can be moved with azimuthally identically distributed force and without wobbling movement relative to one another.
Each working disk 51, 52 supports a working layer 60, 61 on its working surface. The working layers are preferably abrasive pads.
An “abrasive pad” is understood hereinafter to mean a working layer composed of at least three layers, comprising a closed, continuous or interrupted useful layer, facing away from the working disk, in the form of a smooth or structured film, a woven fabric, felt, knitted fabric or individual elements, which contains bonded abrasive and has a useful thickness of more than one abrasive grain layer and at least one part of which makes direct contact with the workpieces to be processed and thereby brings about material removal; a central closed, or at least continuous support layer in the form of a smooth or structured film, a woven fabric, knitted fabric or felt, which supports the useful layer and connects all the elements of the useful layer to form a continuous unit; and a closed, continuous or interrupted mounting layer, which faces the working disk and, over the period of the useable life of the useful layer or a shorter period, determined by the user, forms a force-locking or positively locking composite assembly with the working disk of the grinding apparatus, for example by means of vacuum (sealed mounting layer), magnetically (mounting layer contains a ferromagnetic layer), hook and loop fastener (mounting layer and working disk contain “hook” and “loop”), adhesive bonding (mounting layer is provided with self-adhesive or activatable adhesive layer), etc. The abrasive pad is elastic and can be detached from the working disk by peeling movement. The abrasive pad can, particularly when covering particularly large working disks, be subdivided into up to eight segments, four segments for each working platen, which can be removed or mounted individually to form a gap-free parquetting of the working disk area to be covered.
Suitable abrasive pads are described for example in U.S. Pat. No. 5,958,794. The abrasive pads are preferably structured in the form of small regular units. Preferably, these units consist of regularly arranged “islands” (uniformly elevated regions) and “trenches” (recessed regions). In this case, the islands become engaged with the workpieces and thus bring about material removal. The trenches feed in cooling lubricant and carry away resulting grinding slurry. The absolute size of islands and trenches and the area ratio thereof (supporting area proportion of the working layer) constitute crucial features for the material-removing function of the working layer. The islands of one abrasive pad that is preferably used (Trizact™ Diamond Tile 677XA or 677XAEL from 3M Company) have for example a square shape having an edge length of a few millimeters and are separated by trenches having a width of approximately one millimeter, thus resulting in a supporting area proportion of between 50% and 60%.
The abrasive used in the abrasive pads is preferably diamond. However, other hard substances are likewise suitable (for example cubic boron nitride (CBN), boron carbide (B4C), silicon carbide (SiC, “carborundum”), aluminum oxide (Al2O3, “corundum”), zirconium oxide (ZrO2), silicon dioxide (SiO2, “quartz”), cerium oxide (CeO2) and many others.
However, the abrasive grain can also be directly bonded into the surface of the working disk or be present in the form of an areal covering of the working disk by means of a multiplicity of individual grinding bodies, so-called “pellets”, which are mounted onto the working disk.
The working gap formed between the working layers 60 and 61 fixed on the upper working disk 51 and lower working disk 52, within which gap the semiconductor wafers are processed, is designated by 55 in FIG. 1. | {
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1. Field of the Invention
This invention relates, generally, to devices that produce a waterfall effect at the side of a swimming pool or other landscaping feature such as an artificial rocky cliff. More particularly, it relates to a device that spreads water laterally into a thin sheet to simulate a natural waterfall.
2. Description of the Prior Art
U.S Pat. No. 4,881,280 to Lesikar, entitled "Waterfall Producing Unit For Use In Swimming Pools," shows a device that produces a very smooth waterfall. It employs a deep chamber that receives water from the swimming pool pump, a throat that extends from the deep chamber to the water outlet, a plurality of baffle walls in the throat, and a weir between the deep chamber and the throat. All of these features are supplied to suppress the turbulence of the water exiting the throat to create the simulated waterfall. More specifically, the depth of the deep chamber allows the turbulent incoming water to settle down before it enters the throat of the device. Moreover, the weir that separates the deep chamber from the throat ensures that only a thin layer of water can enter the throat at any one time, and the baffle walls in the throat suppress any residual splashing that may occur therein. The result is a very stable sheet of water that flows from the throat.
In a second embodiment of the Lesikar device, the deep chamber is eliminated and a series of baffle walls is relied upon to suppress splashing and to produce an even film of water. That embodiment has not been seen in commercial models, but it is believed that its arrangement of parts would produce a waterfall having more turbulence than the deep chamber embodiment.
A device that delivers a simulated waterfall to a bathtub is shown in U.S. Pat. No. 4,334,328 to Delepine. However, unlike the Lesikar device, it relies upon two laterally spaced apart sources of water to achieve the lateral spread of water required in a simulated waterfall.
The problem with deep well waterfall-simulating devices of the type first invented by Lesikar is that they must be installed at the time the pool is built because they are too large for retrofit applications. Moreover, such devices are mechanically complex and require substantial assembly time. The art would be advanced if a simple-in-structure and therefore easy to manufacture waterfall creating device could be invented. The ideal device would also have a low profile so that it could be retrofit into existing pools.
Another problem in the swimming pool industry relating to waterfalls is the difficulty of constructing rock waterfalls that will flow as desired down a preselected pathway. The seemingly simple construction task of stacking rocks in a mound and directing water over a preselected side thereof to create a waterfall is anything but simple. Since water finds the path of least resistance, it flows downwardly in unexpected ways, often flowing in a reverse manner such that the resulting waterfall cannot be seen by an observer stationed in front of the rock pile. It often takes years of experience before a waterfall builder can stack the rocks just right to force the water to follow a desired path of travel.
Thus, there is a need in the industry for a structure that could ease the task of rock waterfall construction. The ideal innovation would enable inexperienced workers to build successful waterfalls without going through a time-consuming trial and error procedure.
However, when the teachings and suggestions of the prior art are considered as a whole, it is clear that the invention of the ideal devices needed to fulfill the extant needs would not have been obvious to those of ordinary skill in this art at the time the invention disclosed hereinafter was made. | {
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According to 3GPP (Third Generation Partnership Project), in a radio communication system corresponding to standardized LTE (Long Term Evolution), a radio base station eNB assigns a radio resource (resource block: RB) to a radio terminal UE in radio communication between the eNB and the UE (for example, refer to Non Patent Literature 1). The eNB appropriately changes the resource block that is assigned to the UE. For example, the eNB assigns a wideband resource block to UE that is a transmission destination of a large amount of data, or UE with a high communication priority.
Furthermore, in the radio communication system corresponding to the LTE, one of FDD (Frequency Division Duplex) and TDD (Time Division Duplex) is employed in the radio communication between the eNB and the UE.
Moreover, in an LTE (TDD-LTE) radio communication system employing the TDD, there has been discussed a feature where the eNB calculates an antenna weight according to a reception situation of a sounding reference signal (SRS) that is an uplink radio signal transmitted by the UE, and performs control (beamforming) for adaptively directing a beam toward UE of a transmission destination when transmitting a downlink radio signal or control (null steering) for directing a null toward UE other than the transmission destination, in order to ensure communication quality between the eNB and the UE that is moving.
Under an environment in which a resource block assigned to the UE is appropriately changed, in order to perform the beamforming or the null steering, a frequency band of a resource block to be assigned to the UE needs to be included in a frequency band of SRS. That is, the frequency band of the SRS also needs to be appropriately switched.
To this end, the eNB performs the following process. The eNB transmits, to the UE, an RRC (Radio Resource Control) Connection Reconfiguration message including a parameter related to the transmission content, transmission method and the like of the SRS. The UE transmits an RRC Connection Reconfiguration Complete message to the eNB as a response message, and switches and transmits the SRS according to the parameter. The eNB calculates an antenna weight according to the reception situation of the SRS. | {
"pile_set_name": "USPTO Backgrounds"
} |
A. Field of the Invention
The present invention relates to a computer system and method for modeling and administrating a deferred award instrument plan.
B. Background of the Art
Increased competition among companies has led to the use of stock options as a tool to both recruit and maintain highly skilled labor. Stock options are used as a form of compensation that reward employees for their labor. Employer corporations grant employees the right to purchase stock in the employer at a fixed price. As new products or services are introduced and the stock price rises, the employee""s stock options become more and more valuable. This option, for example, may be given for past service or as incentive for future performance.
When stock options are granted, the price at which the employee has the right to purchase the stock is referred to as the Grant Price. If the options are not exercised in a predetermined period of time, they often lapse. The difference between the Grant Price and the trade price of the stock in the appropriate exchange, (hereinafter xe2x80x9cMarket Pricexe2x80x9d of xe2x80x9cFMVxe2x80x9d) is referred to as the Spread.
There are several different types of stock options that can be granted. Options may be Qualified, commonly referred to as Incentive Stock Options (ISO) that are governed by Sections 422 and 424 of the United States Tax Code. Options may also be Non-Qualified, commonly referred to as Non-Qualified Options (NSO).
There are numerous reasons why it is not desirable to issue too many stock options and/or have them exercised. First, the limited life of most options has cash liquidity ramifications on the employee. The selling of stock to cover stock option costs by key employees can have a negative impact on the company.
A second downside to stock options is taxes. If an NSO is exercised while the employee is alive, the Spread is immediately subject to ordinary income tax. For the stock that is held, the amount of appreciation over the Spread is subject to capital gains taxes when it is ultimately sold. The Spread on the stock that is not held and sold immediately upon exercise of the options is subject to ordinary income tax. Alternative minimum tax is applicable to the Spread of an ISO when it is exercised and capital gains tax is applicable on the difference between the Grant Price and the ultimate sales price of the stock.
If an NSO or ISO is not exercised when the employee is alive, the added burden of estate tax must also be computed. For example, an employee""s family can expect to receive only 12% of the proceeds after taxes on a stock option that has a Market Value that is twice the grant price. The greater number of options awarded the larger the problem becomes. If an employee does not have enough cash to satisfy the Grant Price and taxes associated with an exercise, the employee is forced to sell stock, which only aggravates the tax consequences and reflects poorly on the company.
Many of the issues associated with stock option plans are also present with other deferred compensation programs offered by companies today. Many of these programs also require a significant outlay by the company to compensate or reward an employee. These outlays can detract from a company""s bottom line in the near term. What is therefore needed in the art is a new program, method and apparatus by which a company can compensate its best employees over an extended period, thus minimizing the employees"" tax consequences, while at the same time allowing the company to take maximum tax deductions and recoup many of the costs associated with the administration of these compensation programs.
The present invention is directed to solving the aforesaid problems by providing a unique computer system and computer program for assisting the company""s identification of appropriate employees, through the use of a novel modeling method and apparatus. Another aspect of the invention includes a program that administers a Rabbi Trust unit that permits the employee to benefit from his/her deferred compensation programs, such as stock options and other extended income programs such as life insurance benefits, while having a minimal impact on the company. Further, the present invention includes a system that implements a financial management plan that minimizes tax and maximizes employee benefits, as well as maximizes tax advantages for the company.
Briefly described, the present invention provides an automated Deferred Award Stock Option Plan (DASO(copyright) Plan) that permits employees to benefit from their stock options, or other deferred compensation and income programs, while minimizing the tax consequences and negative impact on the company. The invention also provides a UNIQUE SOLUTION(trademark) Plan (alternatively referred to as a Guaranteed Reduced Estate and Income Tax (GREIT(trademark)) Plan) and a TARGET(trademark) Plan (defined as a GREIT(trademark) Plan for a non-profit/not-for-profit employer, corporation or entity and will also be encompassed hereinafter for simplicity by the term xe2x80x9cUNIQUE SOLUTION(trademark) Planxe2x80x9d), as well as a combination UNIQUE SOLUTION(trademark)/Employee Welfare Benefit (EWB) Plan that additionally allows a company to take maximum advantage of tax deductions and benefits which may be associated with the plans. The present invention comprises a method and system for modeling the programs to determine if the programs are appropriate for a given individual and company, as well as a method of maintaining and operating the individual elements of the invention.
A further object of the present invention is to provide a method and computer system for identifying individuals from a predetermined pool that fit predetermined company goals for inclusion in the DASO(copyright) Plan, UNIQUE SOLUTION(trademark), and the combination UNIQUE SOLUTION(trademark)/EWB Plan.
A further object of the present invention is to provide a method and computer system for the effective and efficient management of a Rabbi Trust designed to implement the DASO(copyright) Plan, UNIQUE SOLUTION(trademark) Plan, and the combination UNIQUE SOLUTION(trademark)/EWB Plan.
The present invention is directed to a method for identifying and administering deferred award instrument plans through a computer system, said method comprising the steps of: identifying at least one participant in said deferred award plan; retrieving financial data related to deferred compensation (such as stock options or other compensation) corresponding to said identified participant and to an employee welfare benefit pursuant to an employee welfare benefit plan for said participant; computing a spread associated with said deferred compensation; establishing a rabbi trust with said spread; determining whether a life insurance policy has been purchased by or on behalf of said participant, said life insurance policy combining features of a deferred compensation plan and an employee welfare benefit plan; determining whether a split dollar agreement has been executed; monitoring and paying at least one premium for said life insurance policy; and notifying said participant that an nth payment associated with said life insurance policy has been paid. After the nth payment has been made, the employee may borrow against the policy with minimal or no tax consequences, in accordance with IRS regulations. When the employee dies, his estate tax may also be reduced as a result of this arrangement.
The present invention is also directed to a method of modeling deferred award instrument plan programs comprising the steps of: inputting models factors; retrieving human resource data; retrieving deferred compensation data and employee welfare benefit data; retrieving fair market value information relating to said data; computing company cost and length of program; and storing said retrieved and computed data. The method may also include converting said human resource data to a deferred award instrument plan format or converting said deferred compensation and/or said employee welfare benefit data to a deferred award instrument plan format.
It is also contemplated that the present invention may include inputting weighing indicators corresponding to said model factors and displaying at least a predetermined portion of said retrieved and stored data based on said weighing indicators.
The present invention is also directed to an apparatus for implementing a deferred award instrument plan comprising: a processor; memory operationally attached to said processor; an input device operationally attached to said processor; a display device operationally attached to said processor; and wherein said memory comprises a deferred award instrument plan program comprising the steps of inputting models factors; retrieving human resource data; retrieving deferred compensation and employee welfare benefit plan data; retrieving fair market value information relating to said data; computing company cost and length of program; and storing said retrieved and computed data.
With these and other objectives, advantages and features of the invention that may become apparent, the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims, and to the several drawings attached herein. | {
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A typical automatic transmission includes a hydraulic control system that is employed to provide cooling and lubrication to components within the transmission and to actuate a plurality of torque transmitting devices to allow synchronization for shifting between multiple gear ratios for transmission output. These torque transmitting devices may be, for example, friction clutches and brakes arranged with gear sets or in a torque converter. The conventional hydraulic control system typically includes a main pump that provides a pressurized fluid, such as oil, to a plurality of valves and solenoids within a valve body. Via multiple valves and multiple solenoid valves individually controlling every clutch control valve, the pressurized hydraulic fluid is directed through a hydraulic fluid circuit to control shifting via torque transmitting devices. The pressurized hydraulic fluid is also directed to various subsystems including lubrication subsystems, cooling subsystems, and torque converter clutch control subsystems. The pressurized hydraulic fluid delivered to the shift actuators is used to engage or disengage the torque transmitting devices in order to obtain different gear ratios.
Known automatic transmissions generally operate in a plurality of modes of operation including out-of-park driving modes and a park mode. The out-of-park driving modes generally include the forward gear or speed ratios (i.e. a Drive mode), at least one reverse gear or speed ratio (i.e. a reverse mode), and a Neutral mode. Selection of the various driving modes is typically accomplished by engaging a shift lever or other driver interface device that is connected by a shifting cable or other mechanical connection to the transmission. Alternatively, the selection of a driving mode may be controlled by an electronic transmission range selection (ETRS) system, also known as a “shift by wire” system. In an ETRS system, selection of the driving modes is accomplished through electronic signals communicated between the driver interface device and the transmission.
While previous transmission control systems are useful for their intended purpose, there is a need for new and improved hybrid transmission hydraulic control system configurations within transmissions which reduce the quantity of control valves and simplify control of the clutch control system, including during transmission default conditions. A default condition is a hydraulic state that the transmission experiences in the absence of electronic control. A transmission in default no longer has the capability to electronically command solenoids to achieve the desired gear state. The default condition may have been intentionally commanded (e.g. when diagnostics indicate corrupt solenoid drivers, corrupt controllers, controller shutdown at high temperatures) or can occur unintentionally due to a hardware failure (e.g. controller failure, wiring harness failure, solenoid driver failure). Accordingly, there is a need for an improved hydraulic control system for use in a hybrid hydraulically actuated automatic transmissions that reduces solenoid valve complexity and can provide different drive states during a default condition. | {
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1. Field of the Invention
The present invention relates to an optical connector.
2. Description of the Prior Art
Various optical connectors have been used for connection or changeover of optical fibers.
For instance, in FIG. 13, there is shown a first optical connector 1 which comprises a rectangular-parallelpiped ferrule 2 having a butt end face 2a at the front portion of the ferrule 2 and positioning pin holes 2b, 2b formed at the opposite sides in a widthwise direction of the ferrule 2, and a fiber ribbon 3 having a plurality of optical fibers 3a, mounted to an rear portion of the ferrule 2. These pin poles 2b and respective optical fibers 3a are arranged in parallel with each other so that they are perpendicular to the butt end face 2a.
In the case where the optical connector 1 is abutted against an another optical connector 1 so as to make an optical communication line connection, a refractive index matching agent is applied on the butt end face 2a so as to prevent a light from being reflected backward, and these optical connectors 1 are abutted against each other by interposing positioning guide pins between pin holes 2b, 2b of the connectors opposed to each other.
Moreover, in order to prevent the foregoing reflection of light from occurring in the butt end face without using the refractive index matching agent, a second optical connector has been used. To give an example of the second optical connector, in FIG. 14, there is shown an optical connector 4 having a butt end face which is inclined with respect to an optical axis of an optical fiber. In an optical connector 4 shown in FIG. 14A, a butt end face 5a at the front portion of a ferrule 5 is formed so that the lower portion of the butt end face 5a is inclined backward by an angle of .theta..sub.1 with respect to a vertical direction. On the other hand, in an optical connector 4 shown in FIG. 14B, the butt end face 5a at the front portion of the ferrule 5 is formed so that a left-hand side of the butt end face 5a is inclined backward by an angle of .theta..sub.2. As described above, the respective butt end faces 5a are inclined with respect to the optical axis of each optical fiber 6a to prevent an end reflection from occurring in the butt end face. In both optical connectors 4, pin holes 5b and respective optical fibers 6a of a ribbon fiber 6 are arranged in parallel with each other, like the optical connector 1.
Also, Unexamined Japanese Patent Publication (KOKAI) No. 58-152212 discloses a third optical connector which can prevent a reflection of light from occurring in an butt end face without using a refractive index matching agent. In that optical connector, an end reflection is prevented from occurring by inclining optical fibers in only the vicinity of the butt end face.
However, the foregoing first optical connector requires wiping off or applying the refractive index matching agent on the butt end face every time that the first optical connector is abutted against an another optical connector. For this reason, there has arisen a problem in that not only an abutting work is troublesome, but also the working place becomes dirty due to the refractive index matching agent.
Further, the foregoing second optical connector has a butt end face which is formed with an inclined plane; therefore, the butt end face is not parallel with a back end of the ferrule. For this reason, in the case where the second optical connector is abutted against an another connector, if a pressing force is applied to the abutting direction, a difference occurs in alignment between butt end faces of these optical connectors abutted against each other. As a consequence, great optical connection loss is caused.
Furthermore, the foregoing third optical connector is constituted so that optical fibers are inclined in only the vicinity of the butt end face. For this reason, there has arisen a problem in that the structure of this connector is complicated; therefore, it takes much time to manufacture such a connector, and such connector is expensive to manufacture. | {
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The present invention relates generally to nanotechnology and in particular to a method of creating metallic and semiconducting nanowires, heterogeneous nanowires, and nanowire assemblies using a technique suitable for mass production.
Conductive, semi-conductive, and insulating nanowires hold great promise for the creation of new devices including small-scale electrical circuit elements, sensors, and the like. Of particular interest in this regard are metallic nanowires. The creation of relatively long molybdenum nanowires is described in a paper authored by the present inventor and published in Science 2001, 290, (5499), 2120-2123 hereby incorporated by reference. This particular fabrication technique employed highly oriented pyrolytic graphite (HOPG) as a substrate. Nanowires were formed through electrochemical step edged decoration (ESED) techniques in which edges on a terraced surface of the HOPG provided a deposition site for the electrochemically deposited nanowires following those edges.
Fabricating devices from nanoconductors can be difficult. In the above ESED technique, the produced nanowires have irregular orientation resulting from the difficulty of controlling the geometry of the step edges on the HOPG substrate. These variations also affect, to a lesser degree, the diameter of the wires produced. Production of the nanowires is further hampered by the fragile nature and expense of the HOPG. HOPG also contains numerous defects that result in particles forming in between the wires.
Nanowires have been fabricated by using a pocket formed under a layer of photoresist between the photoresist and a substrate as separated by a nanothickness layer of nickel. See “Lithographically Patterned Nanowire Electrodeposition”, E. J. Menke et al, Nature Materials 5, 914-919 (2006). This technique makes use of an edge of a larger pattern to define the location of the nanowire eliminating a need for nanoscale line widths in generating the pattern. | {
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This invention relates to apparatus for sealing a hem in a moving web of film and more particularly to the manufacture of draw tape plastic bags.
Bags made of thin polyethylene materials have been used in various sizes. Small bags are used in the packaging of samples and the like. Larger bags are used as shopping bags; and even larger bags are used for containing trash.
A particularly advantageous closure for such a bag includes a draw tape constructed from the same polyethylene material. U.S. Pat. Nos. 3,029,853--Piazzi and 1,125,363--Jortikka are examples of draw tape bags. Such closures have been successfully employed on these bags.
Draw tape closures for large trash bags, and the manufacture of these draw tape trash bags, are described in the related applications identified below.
Forming the hem, into which the tape is inserted, is shown for example, in U.S. Pat. Nos. 2,897 729--Ashton et al 3,058,402--Kugler, 3,058,403--Kugler, and in copending patent applications of applicant's assignee including "METHOD AND APPARATUS FOR FORMING HEMS IN SUPERPOSED PLIABLE PANELS," Boyd et al, Ser. No. 652,255, filed Sept. 20, 1984 now U.S. Pat. No. 4,617,008 and in "HEM FOLDER WITH INTEGRAL TAPE INSERTER FOR MAKING DRAW TAPE BAGS," Herrington, Ser. No. 871,238 filed June 6, 1986.
Draw tape hems have been previously made by various methods. One method is to use a Teflon-coated hot bar which opens and closes against the film in the area of the bag machine where the film starts and stops. The bar closes once during each cycle while the film is stopped. A second method is to blow a series of hot air jets against the film as it travels by. Bag closures for use in the field use a pair of heated belts to produce a machine-direction seal. In the hot bar method, the hot bar is located far downstream from where the tape is inserted into the hem and also where the hem is folded, so there has been an opportunity for the tape and the hem to wander by the time it reaches the sealer. This requires making the hem wider to allow for this wandering movement. This is costly in wasted material, produces a weak tape seal at the side edges of the bag, and also makes a sloppy bag. The hot air sealer can be used on a continuously moving web, but it is very sensitive to wrinkles. The heating of the film by the air jets also causes some wrinkling which cannot easily be prevented since the film is not mechanically constrained. As a result the hem seals made by these techniques are not reliable, particularly where thin films, in the order of one mil, are used.
It is an object of the present invention to seal a hem in a web of film moving at a relatively high speed, such as 250-300 ft./min, where the seal in the hem is produced as close as possible to where the hem is folded and the tape inserted, and while the film is still held flat on the folding surface so there are no wrinkles in the hem.
It is a further object of the present invention to seal hems in the opposing panels of a moving web of folded thermoplastic film in the manufacture of draw tape bags. | {
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As semiconductor devices keep scaling down in size, three-dimensional multi-gate structures, such as the fin-type field effect transistor (FinFET), have been developed to replace planar CMOS devices. A structural feature of the FinFET is the silicon-based fin that extends upright from the surface of the substrate, and the gate wrapping around the channel further provides better electrical control over the channel. | {
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Computers often operate using connections between a main processing board, e.g. a motherboard, and auxiliary equipment. The auxiliary equipment can include a disk drive, such as a xe2x80x9chard drivexe2x80x9d.
Such devices have often been mounted in a bay within a computer. However, removing the hard drive often requires that the end user access the inside of the computer by removing the outer cover. Once inside, it not always intuitive how to remove the hard drive. | {
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1. Field of the Invention
This invention relates to umbrellas and umbrella canopies, but more particularly to an umbrella canopy that can be folded flat, yet when unfolded provides a strong and lightweight structure to ward off wind and rain.
2. Description of the Related Art including information disclosed under 37 C. F. R. .sctn..sctn.1.97-1.98
There are two basic groups of related art that apply to the current invention: conventional umbrellas that use a frame and webbing type construction and umbrellas which use a canopy that combines protective covering and support for the protective covering into one structure. This second group of umbrellas are referred to herein as frameless umbrellas. Frameless umbrellas are typified by those shown in U.S. Pat. Nos. 1,752,821 and 3,205,904 by W. S. Timblin and D. E. Kreachbaum respectively.
Conventional frame and webbing type umbrellas are well known and have been used to protect people from the elements for a number of years. Usually, an umbrella consists primarily of a canopy supported by a frame having ribs. The ribs are hingeably attached to a spreader that is used to furl and unfurl the canopy of the umbrella. The spreader is hingeably attached to a ring that slides along the length of a shank shaft ending in a handle by which the umbrella may be held. As the ring is moved up towards the canopy end of the shank, the canopy of the umbrella unfurls as it is pushed upwards and outwards by the spreader. As the ring is slid down along the shank towards the handle, the ring pulls the spreader downward and inward which furls the umbrella. The ring may have a small slot along one side through which a retractable tab may lodge in order to hold the umbrella in the furled or closed position. Above the canopy at the end of the shank may be an umbrella tip known as a bullet. A sleeve may be used to cover the furled canopy of the umbrella for storage and protection.
The canopy of the umbrella is often made of fabric or some other water resistant material. When unfurled, the canopy fabric is stretched along the ribs of the frame. The ends of the canopy are tied to the rib tips in a taut manner. Variations on the common umbrella also include use of a telescoping handle and a more elaborate framework that allows the canopy to fold in half for compact storage.
Especially with compact umbrellas that are made to fit within a very small space for easy carriage, a significant amount of manual labor is involved in constructing the delicate articulating rib structure that provides the compact umbrella with its small shape and size when furled. This demand for manual labor increases the price of such a compact umbrella with market prices for the most compact conventional umbrellas typically 2 to 3 times that of inexpensive umbrellas of a standard size. Furthermore, with the manufacturing demands of the delicate framework for the compact umbrella, automated processes such as those that might be performed by a machine are limited in use as the individual operations required for the construction of the umbrella demand the flexibility and skill of the human hand.
The structural strength and stability of conventional compact umbrellas is limited due to the delicacy of the framework, and the fact that such framework must be as thin and compact as possible. Delicate frame and webbing type umbrellas are very fragile and easily damaged beyond a usable condition by acts such as mistakenly sitting on such an umbrella when it is left in the seat of an automobile. In addition, the small fragile metal components that make up the framework of a conventional umbrella are easily bent when the umbrella is subjected to harsh conditions. Once these delicate metal components are damaged, the protection provided by the umbrella is reduced and often the umbrella is rendered unusable. A perfect example of such a harsh condition is turbulent wind which does not blow from a constant direction. When the wind changes direction and blows from behind, very frequently a conventional umbrella will blow inside out leaving the user unprotected, and in many cases severely bending the fragile metal components in the umbrella canopy and damaging the umbrella beyond a usable condition.
Although in recent times conventional umbrellas have become relatively compact when compared to their predecessors, they are typically still too bulky to be placed conveniently in a pocket or small purse. As a result, many people still do not carry their umbrellas with them on rainy days to places such as the grocery store where they know that they will have to carry it once they get there. Attempting to carry groceries and an umbrella is a difficult task, especially if the umbrella is wet and cannot be placed in a bag with the groceries. In addition, the cylindrical and relatively long shape of a folded conventional umbrella is inefficient for storage. Most places that a umbrella user may desire to store or carry an umbrella are of a cubical or rectangular shape and in most cases are too small to fit an umbrella. Examples of places where a user may desire to store an umbrella are pockets, briefcases, purses, desk drawers, automobile glove boxes, and all places where a small, flat, rectangular-shaped package would store more efficiently and conveniently than a long cylindrical package. In addition, storing a wet umbrella in these places would be unpractical.
Frameless umbrellas, such as those shown in U.S. Pat. Nos. 3,205,904 and 1,732,867, are constructed of thin flexible material and use an inefficient open cross-section structural configuration. As a result, they cannot provide the level of protection that a conventional umbrella can without being excessively bulky.
It can be seen that advantages can be realized by the manufacture and the making available of a compact umbrella having improved durability; an efficient, high strength structure; and that provides a small lightweight package of a size and shape that is more easily stored and carried when compared to the relevant art. | {
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Turbochargers are well known devices for supplying air to the intake of an internal combustion engine at pressures above atmospheric (boost pressures). A conventional turbocharger, generally designed as reference 10 in FIG. 1, essentially comprises an exhaust gas driven turbine wheel 5 within a turbine section 2 mounted on a rotatable shaft within a turbine housing 4. For instance, in a centripetal turbine the turbine housing 4 defines an annular inlet passageway around the turbine wheel and a generally cylindrical axial outlet passageway 11 extending from the turbine wheel. Rotation of the turbine wheel rotates a compressor wheel mounted on the other end of the shaft within a compressor housing 6 of the compressor section 2. The compressor wheel delivers compressed air to the intake manifold of the engine, thereby increasing engine power.
Turbochargers incorporating wastegates are also well known, as illustrated in FIG. 1. A wastegated turbocharger has a bypass passageway between the exhaust inlet and exhaust outlet portions of the turbine housing to enable control of the turbocharger boost pressure. A wastegate valve assembly 13 is located in the passageway and is controlled to open the passageway when the pressure level of the boost air increases to a predetermined level, thus allowing some of the exhaust gas to bypass the turbine wheel preventing the boost pressure from rising further. The wastegate valve 13 is generally actuated by a pneumatic actuator 22 operated by boost air pressure delivered by the compressor wheel. The pneumatic actuator 22 may comprise a spring loaded diaphragm or sliding seal housed within a canister 24 (referred to as an actuator can) which is mounted to the compressor housing 6. The diaphragm seal acts on a connecting rod 26 which actuates the wastegate valve assembly 13. The actuator can 24 is connected to the compressor outlet via a hose to deliver boost air to the can which acts on the diaphragm (or sliding seal) to oppose the spring bias. The spring is selected, and the actuator and wastegate valve initially set, so that under low boost conditions the wastegate valve 13a remains closed. However, when the boost pressure reaches a predetermined maximum the diaphragm seal is moved against the action of the spring and operates to open the wastegate valve 13a (via the connecting actuator rod) thereby allowing some exhaust gas to bypass the turbine wheel.
In these types of conventional wastegate valves, the pressure at which the wastegate valve begins to open (the “lift off pressure”) is critical to the operation thereof. Accordingly, the wastegate valve must be very carefully set when the pneumatic actuator 22 and wastegate valve assembly 13 are assembled to the turbocharger. The precise actuator can 24 pressure, at which the diaphragm begins to move, is dependent upon the preload of the spring used. Unfortunately, the variation in the manufacturing tolerances of springs means that variations in spring rate from one spring to the next is likely, and it is necessary to calibrate each turbocharger, individually, to determine the lift off pressure.
One method of carrying out the initial set up of the conventional actuator assembly described above, is a process known as “weld to set”. The actuator can 24, actuating rod 26 and actuator lever 28 are pre-assembled, and mounted to the turbocharger 10. The wastegate valve 13a is then clamped shut from within the turbine housing 4 and the actuator can 24 is pressurized to the desired lift off pressure. With the diaphragm, actuator rod 26 and valve 13a thus held in their respective relative positions immediately prior to lift off, the end of the actuator lever is welded to the valve stem. Accordingly, any increase in the pressure supplied to the actuator above the predetermined lift off pressure will cause the valve 13a to open.
A known alternative to the above is to use an adjustable length actuator rod, typically comprising a threaded rod and rod end. The set point is achieved by adjusting the length of the rod, either by turning the rod end or a nut captured in the rod end assembly. Even using this method, it is still necessary to calibrate each turbocharger, individually, to determine the lift off pressure.
The assembly process and combined calibration process is very time intensive. Moreover, once assembled it is difficult to replace a faulty pneumatic actuator 22 and/or wastegate valve assembly 13. Conventional practice is to replace the entire turbocharger assembly, since they come pre-calibrated with an installed wastegate actuator 20 and wastegate valve assembly 13. This is an expensive replacement. | {
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There are various constructions of contact lens storage devices which include a separate storage compartment for storing a rinsing solution, cleaning solution or other solution to be applied to the contact lenses. All such solutions which can be applied to contact lenses to clean, rinse, sterilize, condition or otherwise treat the contact lenses will be referred to herein as a contact lens solution.
One such storage device is shown in U.S. Des. Pat. No. 390,356 (Fortier) and includes a cylindrical squeeze-bottle of contact lens solution with nozzles at both ends, a cylindrical contact lens case mounted on each end of the solution bottle via threads located on each end and a cap for covering each contact lens case. Each contact lens case appears to be fillable with contact lens solution from the squeeze-bottle by squeezing the solution bottle.
Another contact lens storage device is shown in U.S. Pat. No. 4,721,124 (Tuerkheimer et al.) and includes a container for housing a pair of lens carriers which hold a pair of contact lenses and a base/pump housing connected to the bottom of the container for retaining cleaning fluid. A pump mechanism propels the cleaning fluid into the cleaning chamber. In use, the base/pump housing is filled with contact lens solution and then the contact lenses are placed into the lens carriers. The bottom wall of the base/pump housing is pressed to force contact lens solution through apertures into the lens carriers.
U.S. Pat. No. 5,347,674 (Gabbert) describes another contact lens storage device including a pair of lens containers and a fluid reservoir for housing contact lens solution. The reservoir is in fluid communication with the lens containers such that the contact lens solution may travel through a channel into the lens containers. The fluid reservoir can be replenished with contact lens solution via a hole formed in the fluid reservoir.
U.S. Pat. No. Des. 331,588 (Ives) shows a combination vial, tray and case for contact lenses and contact lens solution.
U.S. Pat. No. 5,381,889 (Amend) describes a container for contact lenses and for a supply of contact lens fluid having a base body with a receptacle for a removable contact lens case, a fluid chamber for the contact lens fluid, and a metering connector fastened on the fluid chamber to purportedly fill the contact lens ease with fluid. | {
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This invention relates to an ostomy coupling.
Ostomy couplings are used to connect and disconnect a bag for receiving a stomal discharge to and from a medical grade adhesive pad which is applied to the peristomal area of the skin of the wearer. Many designs of ostomy coupling are known. One which has enjoyed considerable commercial success is described and claimed in U.K. Patent No. 1,571,657.
An ostomy coupling in which unlocking of two coupling parts is achieved by deforming a ring in the form of a closed loop is disclosed in our U.K. Patent Application No. 9409037.0, filed May 6, 1994.
It has been proposed by Kubo, in Japanese Utility Model No. 62-11610, published February 1985, that an ostomy device should have a double female ring structure which can interengage with a male ring. The male ring may be on the bag and the female ring on a skin-attachable adhesive pad, or vice-versa. The outer ring on the female ring is circular and flexible and has a pair of inwardly-extending catches at opposite ends of a diameter. By pressing on two diametrically extending lugs, whose diameter is substantially at right angles to the diameter joining the catches, the outer female ring is deformed so that the catches are caused to move radially outwardly, so permitting separation of the two coupling parts.
This arrangement, though perhaps operable in theory, has serious disadvantages in practice, for example (i) to connect or disconnect it is necessary to hold the coupling at four places, approximately spaced at 90.degree. intervals around the periphery, (ii) pressing on two diametrically opposed regions will tend to bend the coupling out of its normal plane and the forces applied may easily cause the body side pad to be partially (or wholly) detached from the skin of the wearer, also the need to press in both ends of the diameter fully, and simultaneously, means that releasing the bag-side coupling is subject to uncertainty, (iii) the repeated attachment and withdrawal of the bag-side coupling part will cause the o-ring (provided to prevent escape of excreted matter between the male and female rings) to become worn, so compromising its sealing qualities with potentially highly embarrassing and undesirable results, (iv) the wearer may find it difficult to determine whether or not the two coupling parts are properly engaged, (v) the accuracy and forces needed for manipulation to connect or disconnect will be well beyond the capability of an infirm, confused, elderly or impatient wearer; (vi) it is hard to be sure that the appliance is properly locked; and (vii) in the case of large sizes, the old and infirm will find it physically difficult to span with their hand and push in diametrally opposed regions of the ring.
In U.S. Pat. No. 5,180,377 there is disclosed an ostomy coupling in which a bag-side coupling attached to an ostomy pouch can be held onto to a body-side member by a third member which is substantially circular, deformable, and clamps or grips the bag side coupling when it is tightened. In practice, the diameter of the third member is reduced by operation of a mechanical control mechanism, some of whose parts are attached to the third member. While it may be true, as the patentee states, that a sealed mechanical connection of bag- and body-side couplings can be achieved using such a mechanism, the overall construction is relatively complex, which of course affects manufacturing costs.
PCT published Applications Nos. WO91/01118 and WO91/01119 relate to an ostomy coupling and to a ring for locking such a coupling. The ring has two free ends which are manually pulled together to tighten the ring circumferentially around bag- and body-side coupling parts whose structure is designed in various ways so that they can inter-engage. This results in a variety of relatively complex designs, likely to be costly to manufacture. Manipulation of such a coupling will potentially give rise to difficulties for infirm, elderly, or non-dexterous persons.
It is an aim of this invention to provide improved designs of ostomy couplings which embody a springy or resilient split ring as a locking ring. That is, the ring is generally circular in form but has a single gap therein, subtending a small angle, e.g. 5 to 15.degree.. | {
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1. Field of the Invention
The present invention relates to an indirect radial ray detector and a method for manufacturing the same.
2. Description of the Related Art
As new-generation image detectors for X-ray diagnosis, an attention has been paid to planar-shaped X-ray detectors using an active matrix or a solid-state image sensing device such as CCD or CMOS. When such X-ray detectors are irradiated with X-rays, X-ray photographed images or real-time X-ray images are output as digital signals. Since the X-ray detectors are solid-state detectors, they are greatly expected from viewpoints of image quality performance and stability, and thus considerable research and development are being promoted.
The X-ray detectors using active matrix are developed mainly for photographing chest regions to collect still images with comparatively large radiation dosage and general photographing, and have been commodified in recent years. The commodification of the X-ray detectors are assumed in the near feature in order to apply them to the fields of circulatory organs and digestive organs in which real-time moving images of not less than 30 frames per second at transmitted ray amount should be realized with higher performance. In the application to the moving images, improvement of the signal-to-noise ratio and a real-time processing technique for very small signals become important terms of the development.
The X-ray detectors using solid-state image sensing device such as CCD or CMOS have been commodified in recent years for nondestructive inspection in the industrial field where still images are collected at large radiation dosage or dentistry where the detectors are put into mouth capsules and still images are collected. In such X-ray detectors, the improvement of the signal-to-noise ratio and the real-time process for very small signals, miniaturization of the X-ray detectors, and improvement of reliability as well as the application to moving images are important terms of the development.
The X-ray detectors are roughly classified into two systems including a direct system and an indirect system. The direct system is a system which converts X-rays directly into a charge signal by means of a photoconductive film made of a-Se or the like. On the other hand, the indirect system is a system which once converts X-rays into visible light by means of a scintillation layer and then converts the visible light into a signal charge by means of an a-Si photodiode, CCD or CMOS.
In the conventional indirect X-ray detectors, as shown in FIG. 4, a light receiving section 2 having a plurality of photoelectric conversion elements 2a for converting visible light into an electric signal is formed on a photoelectric conversion substrate 1, and substrate-side electrode pads 3 which are electrically connected to the photoelectric conversion elements 2a, respectively, are formed outside the light receiving section 2. A scintillation layer 4 which converts X-rays into visible light is formed on the light receiving section 2 of the photoelectric conversion substrate 1, and a reflection layer 5 which heightens use efficiency of the converted visible light is formed on the scintillation layer 4.
The photoelectric conversion substrate 1 is fixed onto a base 7 having base-side electrode pads 6 for external connection, and the substrate-side electrode pads 3 and the base-side electrode pads 6 are electrically connected by interconnects 8. The substrate-side electrode pads 3, the base-side electrode pads 6 and the interconnects 8 are coated with a protective layer 9 composed mainly of a resin material in order to achieve reliability of the X-ray detectors. In order to protect the scintillation layer 4, the surfaces of the scintillation layer 4 and the reflection layer 5 are coated with a protective layer, not shown, and a protective cover, not shown, is provided to an opening of the base 7 so that the inside of the base 7 is sealed.
Normally, in the indirect X-ray detectors, the property of the scintillation layer is structurally important, and high-luminance fluorescent materials composed of a halogen compound such as CsI or an oxide compound such as GOS are mostly used as the scintillation layer in order to improve output signal intensity with respect to incident X-ray. Further, in general, a high-density scintillation layer is often formed uniformly on a photoelectric conversion substrate according to a vapor growth method such as a vacuum deposition method, a sputtering method and a CVD method.
However, when the halogen compound such as CsI as the high-luminance fluorescent material is used for the scintillation layer, reactivity of a halogen element such as iodine is high, and thus the scintillation layer reacts with electropositive elements in the photoelectric conversion elements, the substrate-side electrode pads, the base-side electrode pads and the interconnects for electrically connecting these pads in contact with the scintillation layer. As a result, the photoelectric conversion elements and the like are corroded, and thus various properties and reliability of the X-ray detectors deteriorate.
As shown in FIG. 4, the substrate-side electrode pads 3, the base-side electrode pads 6 and the interconnects 8 for electrically connecting these pads 3 and 6 are coated with the protective layer 9, so that the corrosion can be prevented. Since the protective layer 9 is made mainly of a resin material, its X-ray absorptance is lower than that of the scintillation layer 4, and thus the reliability might deteriorate as a result of X-ray resistance.
On the other hand, as to the photoelectric conversion elements, although the indirect X-ray detectors reduces interlayer peeling of the scintillation layer, a transparent layer made of polyimide or the like is formed on the surface of the light receiving section of the photoelectric conversion substrate, and the scintillation layer is formed on the transparent layer so that the corrosion can be prevented (for example, see page 3 and FIG. 1 in Jpn. Pat. Appln. KOKAI Publication No. 2001-188086). | {
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1. Field of the Invention
The field of the invention is data processing, or, more specifically, methods, apparatus, and products for thermal-aware source code compilation.
2. Description of Related Art
The development of the EDVAC computer system of 1948 is often cited as the beginning of the computer era. Since that time, computer systems have evolved into extremely complicated devices. Today's computers are much more sophisticated than early systems such as the EDVAC. Computer systems typically include a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input/output devices, and so on. As advances in semiconductor processing and computer architecture push the performance of the computer higher and higher, more sophisticated computer software has evolved to take advantage of the higher performance of the hardware, resulting in computer systems today that are much more powerful than just a few years ago.
During operation of a computer, memory modules such as Dual In-line Memory Modules (DIMMs), may generate a large amount of heat. Heat generation may cause degradation and eventually failure of DIMMs over time. Current program execution may create a disproportionate distribution of heat generation among many DIMMs or even among modules of one DIMM. That is, in a memory system that includes a number of DIMMs, a subset of the DIMMs may be accessed many more times than other DIMMs in the system. This disproportionate accessing may cause the subset of DIMMs to generate far more heat over time than other DIMMs. Such disproportionate heat generation may effect degradation of the subset of DIMMs more quickly than the other DIMMs in the system. That is, the operating life of each DIMM in the subset of DIMMs that is accessed more frequently is consumed much more quickly than the operating life of each of the other DIMMs. It would be useful, therefore, to distribute heat generation in a more balanced, even manner amongst all DIMMs in a subsystem. | {
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The quality and performance of manufactured components is directly related to conformance with part specifications. Conformance with specifications, in turn, is affected by the number of manufacturing processes the component is subjected to, and the cumulative effect of dimensional tolerance or “play” of different specifications. Internal gears, for instance, are typically formed, cut or otherwise provided with an initial inner diameter bore and an outer diameter. Then the gears are subjected to an external broaching process at the outer diameter and then an internal broaching process at the inner diameter. Because both of these processes are piloting operations, in which a work tool is directed axially through the component, specification tolerances at the pre-broach inner diameter are tight to ensure a close fit with the tool and minimize cumulative stack-up of dimensional errors. In fact, the diameter of the pilot section of the broach tool is typically only 0.030 mm-0.050 mm under the smallest acceptable work piece inner diameter. The need for tight dimensional tolerance increases component cost. Additionally, after the external broaching process and prior to the internal broaching process, the component is typically turned, i.e., re-cut, at the inner diameter bore to ensure acceptable concentricity of the inner bore and newly-broached outer diameter. Significant capital cost is associated with this additional process step. Working performance of the finished work piece will be enhanced and the number of scrapped components will be reduced if concentricity of the inner diameter, the outer diameter and the work tool can be controlled with a minimal number of process steps. | {
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The present invention relates to a process for the preparation of spun fleeces made from thermoplastic synthetic resins, hereinafter termed thermoplastics, in which fleeces the properties, particularly the tensile strength thereof, are improved.
Spun fleeces or spunbonded webs, which are built up of virtually continuous filaments of thermoplastics which are laid down in approximately random arrangement, have been known for a considerable time. Generally, they are produced by laying down the filaments, immediately after they have been spung and stretched, mainly by means of air. The degree to which remnants of parallel fiber bundles are present varies with the lay-down method used. An ideal, completely unorientated random arrangement is mostly not achieved, so that such fleeces or webs almost always have a higher tensile strength in one direction than in the direction at right angles thereto.
For a number of applications, for example, in civil engineering, it is not the strength in one direction, but the strength in all directions, which matters. This means that when the material is used, the lowest tensile strength is the determining factor, so that the thickness of the web must also be selected in accordance with the lowest tensile strength. This in turn means that it becomes more expensive to use the fleece, a fact which stands in the way of certain large industrial applications.
United Kingdom patent specification No. 1,535,988 describes a process in which the properties of staple fiber webs wherein the individual fibers are orientated at right angles to the machine direction are improved by stretching the webs first in the longitudinal direction, then needle-punching them, then again stretching them in the longitudinal direction and finally stretching them in the transverse direction. This increases the dimensional stability and strength of these webs.
Also, it is known from United Kingdom patent specification No. 1,371,863 that in the case of non-consolidated randomly arranged staple fiber webs consisting of relatively short fibers, which have been provided with a regular pattern by means of mechanical or fluid forces, the transverse tensile strength may be improved by stretching in the transverse direction, accompanied by shrinkage in the longitudinal direction, without this stretching destroying the pattern consisting of regular thick and thin areas. Rather, the pattern may be completely reconstituted by another aftertreatment with fluid forces, which bring about a reorientation of the relatively short fibers.
Finally, West German Offenlegungsschrift No. 1,635,634 discloses a method of improving the longitudinal tensile strength of webs, which as a result of plaiting-down have a strong orientation in the transverse direction, by stretching them in the longitudinal direction during needle-punching, This stretching, which at the same time results in an uncontrollable reduction in width, is intended to have the effect that the fiber pile, which in the plaiter is laid down with the layers at angle of 10.degree. to 15.degree. to one another, is so distorted during the first needle-punching operation that the fibers ultimately settle at an angle of 45.degree. to one another, and are fixed in this position.
This process, which may be carried out, during needle-punching, only by breaking it down into numerous individual small stretching steps, requires expensive equipment, since, for example, the needle-punching machine must work with a low punching speed but a high output speed and furthermore should execute a side-to-side motion since otherwise stripes are produced in the web. This Offenlegungsschrift also points out that simple stretching of the plaited-down web is not possible since it results in the formation of thin areas which tear on further stretching.
Stretching to improve the properties also has been proposed for webs of continuous filaments. According to United Kingdom patent specification No. 1,213,441, webs which are welded or glue-bonded at the cross-over points are stretched, in at least one direction, to the extent that the surface area increases by a factor of up to about 15. Since the cross-over points in the webs used for this process are rigidly fixed, this treatment results in a stretching of the individual filaments, which vary greatly in individual gauge, and results in fluctuations in gauge, of the individual filaments, by a power of ten. Stretching in this process is effected over a heated brake pad.
It now has been found that the tensile strengths of a spun fleece in which the filaments are in approximately random arrangement may be substantially equalized in directions at right angles to one another, the lower tensile strength in one of the two directions being substantially increased, without however the filaments themselves being stretched and the filament gauge becoming non-uniform, if a needle-punched fleece is stretched, at an elevated temperature, in the direction which has the lower tensile strength.
As used herein the term "random arrangement" is intended to mean the substantial absence of any anisotropy in the arrangement of the individual filaments
As a result of this stretching step, the lower tensile strength is increased though at the same time the surface area of the fleece is enlarged at the expense of the weight per square meter. The fact that nevertheless a higher minimum tensile strength is achieved now offers the possibility of substantially more economical use of the fleece, above all in underground civil engineering, such as road making, tunnel construction, construction of embankments and hydraulic civil engineering, since what matters in these applications is virtually only the force-elongation characteristics, but not the weight of the web per square meter, and accordingly larger surfaces may be covered with the same weight of a fleece material.
The fact that a needle-punched fleece, in which the cross-over points are not so consolidated that they will not open up, may be reinforced is surprising since it was to be expected that any thin areas which might be present would be accentuated or that holes might even appear. However, this is not the case. On the contrary, a more uniform distribution of the randomly arranged filaments is achieved, with filaments lying in loops passing into the stretched position with increasing degree of stretching, and thereby imparting a higher strength to the fleece. However, this may be achieved only if the stretching is carried out within a certain temperature range which depends on the crystallite melting point. | {
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1. Field of the Invention
The present invention concerns devices for analysing end tuning motor vehicles, and in particular a remotely controlled device for rotating the steering-wheel and then taking it back to the starting position.
It is known that the front steering wheels of motor vehicles require a periodical check and truing operation of their toe-in in order to verify the correctness of the various angles characterizing the forecarriage kinematic mechanism. In carrying out said toe-in operation, the front wheels are repeatedly steered one way and the other by means of the steering-wheel, in order to allow also the alignment of the steering-wheel spiders with the wheels, so that the driver is not obliged, to keep the steering-wheel lightly rotated on one side to go straight.
This rotation of the steering-wheel is usually carried out manually by the person carrying out the toe-in operation, which blocks the steering-wheel in the desired position by means of a suitable device, or by an assistant thereof whim rotates and blocks the steering-wheel according to the instructions of the operator which is under the vehicle,
2. The Prior Art
An example of a remotely controlled apparatus capable of rotating the steering wheel of an automobile is disclosed in U.S. Pat. No. 3,465,577. However, this apparatus is mainly intended to manipulate the control pedals and the gear shift lever, while having the optional capability of rotating the steering wheel by means of a pair of rollers having a soft surface to contact the steering wheel ring. It is apparent that this arrangement does not prevent the rollers from sliding on the ring, particularly at the end of the steering run. Moreover, it can not be applied to steering wheels having a shape other than exactly circular (e.g. oval or rounded square), otherwise the rollers would not contact the ring properly along certain arcs of the rotation. | {
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In recent years, many attempts have been made to develop ceramic materials for electronic components such as piezoelectric components. In particular, lead-free ceramic materials, which contain no lead, are being investigated in consideration of the environment.
Among the lead-free ceramic materials, niobate compounds, particularly alkali niobates, have high Curie points and large electromechanical coefficients and therefore are expected to be possible ceramic materials for piezoelectric components.
Since the alkali niobates are usually deliquescent, there is a problem in that it is difficult to store and control them.
A piezoelectric ceramic composition containing Bi and an alkali niobate, which is a principal component, has been proposed (Patent Document 1).
As disclosed in Patent Document 1, the addition of Bi to the alkali niobate is effective in preventing the deliquescence of the piezoelectric ceramic composition. This enhances the storage stability of the piezoelectric ceramic composition.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2005-281013 | {
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The present invention relates to a universal platform suitable for software defined radio and capable of handling multiple radio standards.
After the first technical paper was presented in 1992, software defined radio (SDR) has been receiving much attention among researchers working on wireless communications (refer to J. Mitola III, D. Chester, S. Haruyama, T. Turletti, and W. Tuttlebee, xe2x80x9cGlobaliazation of Software Radio,xe2x80x9d IEEE Communications Magazine, vol.37, no.2, pp.82-83, February 1999, and R. Kohno, xe2x80x9cPrespective of Software Radio: Spatial and Temporal Communication Theory Using Adaptive Array Antenna for Mobile Radio Communicationsxe2x80x9d, Proceeings on Microwave Workshops and Exhibition (MWE ""97), December 1997). There is a conceptual reason and a technical reason behind this popularity (refer to J. Mitola III, xe2x80x9cTechnical Challenges in the Globalization of Software Radio,xe2x80x9d IEEE Communications Magazine, vol.37, no.2, pp.84-89, February 1999).
The conceptual reason is that various wireless standards have been established through generations of wireless communication systems. Even in the same generation, several standards have been created in different regions.
As an example, the standardization efforts surrounding IMT2000/UMTS have tried to resolve the dispute over what the third generation standard should entail. Despite all of this, it still seems as if three slightly varying code division multiple access (CDMA) standards will be introduced in the near future.
For wireless local area networks (LAN), not only IEEE standards, but also de facto standards such as Bluetooth have gained wide acceptance among companies all over the world. Thus, a multiband multimode radio system is required to create a comfortable mobile computing environment. The reconfigurability of SDR is the answer to this problem.
The technical reason behind the popularity of the SDR concept is the development of reconfigurable devices for signal processing such as digital signal processors (DSP) and field programmable gate arrays (FPGA). The latest DSP""s operate at speeds up to 1.1 GHz and offer performance of nearly 9 billion instructions per second. FPGA""s can now provide densities of up to 2 million gates with low power consumption. These numbers are ever improving (refer to M. Cummings and S. Haruyama, xe2x80x9cFPGA in the Software Radio,xe2x80x9d IEEE Communications Magazine, vol.37, no.2, pp.108-112, February 1999, and F. J. Harris, xe2x80x9cConfigurable Logic for Digital Communications: Some Signal Processing Perspectivexe2x80x9d, IEEE Communications Magazine, vol.37, no.8, pp.107-111, August 1999).
Therefore, the real challenges facing SDR are the RF front-end, which is able to use the reconfigurability of the signal processing devices mentioned above and providing multimode and multiband communications.
In order to realize a multimode multiband SDR, the RF front-end should be able to support a wide range of frequencies and bandwidths. This task may be difficult with conventional RF front-end architectures (H. Tsurumi and Y. Suzuki, xe2x80x9cBroadband RF Stage Architecture for Software-Defined Radio in Handheld Terminal Applications,xe2x80x9d IEEE Communications Magazine, vol.37, no.2, pp.90-95, February 1999).
FIG. 1 is a block diagram of a conventional heterodyne receiver.
The heterodyne receiver 10 of FIG. 1 comprises a receiving antenna 11, a low noise amplifier (LNA) 12, a radio-frequency (RF) filter 13, an RF mixer 14, an RP use local oscillator 15, a first intermediate-frequency (IF) filter 16, an IF mixer 17, an IF use local oscillator 18, a second IF filter, an automatic gain controlled (AGC) amplifier 20, and an analog-to-digital converter (ADC) 21.
This architecture requires frequency-dependent passive components such as a dielectric filter 13 in the RF stage and surface acoustic wave (SAW) filter 16 in the first IF stage. A ceramic or crystal filter 19 is also needed in the second IF stage. The center frequencies and bandwidth of these filters 13, 14, and 19 are not flexible and not wide enough to support a multiband radio receiver.
Though switched capacitor filter banks and precision direct synthesis may be a choice to achieve wider bandwidths and programmability, they are not applicable to mobile terminals due to their size and weight.
Thus, the candidate for the RF front-end for SDR is the direct conversion (DC) principle.
FIG. 2 is a block diagram of a conventional direct conversion receiver.
The direct conversion receiver 30 of FIG. 2 comprises a receiving antenna 31, an LNA 32, RF mixers 33 and 34, an RP use local oscillator 35, a n/2 phase shifter 36, low-pass filters (LPF""s) 37 and 38, AGC amplifiers 39 and 40, and ADC""s 41 and 42.
In the direct conversion receiver 30 of FIG. 2, the received signal is down-converted directly to baseband by the quadrature mixer. The down-converted in-phase and quadrature (IQ) signals are prefiltered by the anti-aliasing LPF""s 37 and 38 with variable cutoff frequency. They are converted to digital signals by IQ ADC""s 41 and 42 and fed to the digital stage. The desired signal is selected by the software defined filter with programmable cutoff frequency.
The DC technique inherently has no image response, and the fixed-frequency image rejection filters can be eliminated. Furthermore, the anti-alias LPF can be designed with active, variable-bandwidth filters such as a switched capacitor embedded in an LSI chip.
In the conventional DC technique, the mixer has been used, however, in general it is difficult to design the mixer for a wide bandwidth. Therefore, if the conventional DC technique is applied to the software wireless system, improvement is necessary in point of widening the bandwidth.
Further, in the conventional direct conversion receiver, a sufficiently high local power is necessary in order to make the mixer operate with satisfactory characteristics. This invites an increases of power consumption of the receiver. Especially, when the carrier frequency is high, it is difficult to obtain a lower power consumption and a high local output power.
An object of the present invention is to provide a universal platform for software defined radio capable of solving the DC offset problem and supporting very wide bandwidths.
According to the first aspect of the present invention, there is provided a universal platform for software defined radio, comprising an n (n being an integer of 3 or more)-port receiver including: a first input terminal receiving as input a received signal, a second input terminal receiving as input a local signal, a generating means for generating two signals having a phase difference based on at least one signal between the received signal input from the first input terminal or the local signal input from the second input terminal and including at least one output terminal for outputting the generated signal, and at least one power detector for receiving as input the output signal from the output terminal and detecting the signal level of the input signal; and a converter for converting the output signal of the power detector to a plurality of signal components included in the received signal or the local signal.
According to a second aspect of the present invention, there is provided a universal platform for software defined radio, comprising an n (n being an integer of 3 or more)-port receiver including a first input terminal receiving as input a received signal, a second input terminal receiving as input a local signal, a generating means for generating two signals having a phase difference based on at least one signal between the received signal input from the first input terminal or the local signal input from the second input terminal and including at least one output terminal for outputting the generated signal, and at least one power detector for receiving as input the output signal from the output terminal and detecting the signal level of the input signal; at least one analog-to-digital (A/D) converter for converting the output analog signal from the corresponding power detector to a digital signal, and a digital signal processing part for converting the output signal of the power detector through the A/D converter to a plurality of signal components included in the received signal or the local signal.
In the present invention, the digital signal processing part compensates for the non-linearity of the power detector.
Further, in the present invention, the power detector preferably comprises a first field effect transistor receiving the input signal at its gate, a second field effect transistor with a source connected to a source of the first field effect transistor, a first gate bias supplying circuit for supplying a gate bias voltage to the gate of the first field effect transistor, a second gate bias supplying circuit for supplying a gate bias voltage to a gate of the second field effect transistor, a current source connected to the connecting point of the sources of the first field effect transistor and the second field effect transistor, a drain bias supplying circuit for supplying a drain bias voltage to the drains of the first field effect transistor and the second field effect transistor, a first capacitor connected between the drain of the first field effect transistor and a reference potential, and a second capacitor connected between the drain of the second field effect transistor and the reference potential, and wherein the voltage difference between the drain voltage of the first field effect transistor and the drain voltage of the second field effect transistor is processed as a detection output.
Further, in the present invention, preferably, the first field effect transistor and the second field effect transistor have substantially the same characteristics, the drain bias supplying circuit includes a first drain bias use resistance element connected between the drain of the first field effect transistor and a voltage source and includes a second drain bias use resistance element connected between the drain of the second field effect transistor and a voltage source, a resistance of the first drain bias use resistance element and a resistance of the second drain bias use resistance element are set to substantially equivalent values, and a capacitance of the first capacitor and a capacitance of the second capacitor are set to substantially equivalent values.
Further, in the present invention, preferably, when a gate width of the first field effect transistor is Wga and a gate width of the second field effect transistor is Wgb, the ratio Wga/Wgb is set to N, the drain bias supplying circuit includes a first drain bias use resistance element connected between the drain of the first field effect transistor and a voltage source and includes a second drain bias use resistance element connected between the drain of the second field effect transistor and a voltage source, a resistance Ra of the first drain bias use resistance element and a resistance of the second drain bias use resistance Rb element are set so as to satisfy the condition Ra/Rb=1/N, and a capacitance of the first capacitor and a capacitance of the second capacitor are set to substantially equivalent values.
Further, in the present invention, the power detector preferably alternatively comprises a first field effect transistor receiving the input signal at its gate and with a source connected to a reference potential, a second field effect transistor with a source connected to the reference potential, a first gate bias supplying circuit for supplying a gate bias voltage to the gate of the first field effect transistor, a second gate bias supplying circuit for supplying a gate bias voltage to a gate of the second field effect transistor, a drain bias supplying circuit for supplying a drain bias voltage to the drains of the first field effect transistor and the second field effect transistor, a first capacitor connected between the drain of the first field effect transistor and a reference potential, and a second capacitor connected between the drain of the second field effect transistor and the reference potential, and wherein the voltage difference between the drain voltage of the first field effect transistor and the drain voltage of the second field effect transistor is processed as a detection output.
According to the present invention, for example, an RF signal is received and input to the generating means of the n-port receiver through the first input terminal, while the local signal generated, for example, by a local oscillator is input to the generating means of the n-port receiver through the second input terminal.
In the generating means, two signals having a phase difference based on the received signal or the local signal are generated. The generated signal is output to the power detector from the output terminal (port).
In the power detector, the input signal level is detected. The detected signal is, for example, converted from an analog to digital format and fed to the digital signal processing part.
In the digital signal processing part, the converted digital signal of the power detector is converted to a plurality of signal components included in the received signal or the local signal. | {
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1. Field of the Invention
The present invention relates to data converters, and more particularly to delta sigma modulators.
2. Description of the Related Art
Analog to digital conversion is widely used in many circuit applications. Such application environments include hearing aids, cellular telephones, and other circuits which require conversion of audio information into a digital form. The single-loop higher order delta-sigma modulator based analog to digital converter (ADC) has recently found a significant application area in audio circuits such as these. Delta-sigma modulators combine the quantization noise reduction and eased analog circuitry benefits of oversampling ADC""s with the benefit of noise shaping to achieve a high resolution ADC.
Increased accuracy in ADC""s is continuously sought after so as to improve the performance of the circuit wherein the ADC is utilized. In addition to improved accuracy and resolution, power consumption in battery powered devices implementing a delta-sigma converter can be of significant concern.
A delta-sigma modulator employing a single loop, fourth order architecture comprises an input signal section, an output signal section, four integration stages connected in a cascaded configuration and having a signal path, at least one feedback path from the output signal section, and a feed-forward path, connected to the input signal section and to the signal path prior to a fourth integration stage. The feed-forward path includes a differentiator, which is connected to the signal path prior to the fourth integration stage. The delta-sigma modulator can be implemented in, for example, an analog to digital converter.
In one embodiment, at least one of the integration stages has a ratio of gain bandwidth product to sampling frequency of less than about 0.2 times a resolution of the delta-sigma modulator.
A method of improving error processing in a fourth order delta-sigma modulator having four integration stages comprises connecting an input signal feed-forward path to the signal path prior to a fourth integration stage. The method further comprises differentiating an input signal along the feed-forward path.
A fourth order delta-sigma modulator, for use in an analog to digital converter, comprises an input signal section, an output signal section, a plurality of integration stages connected in a cascaded configuration, a feed-forward path coupled to the input signal section and connected to the signal path prior to a last of the plurality of integration stages. The feed-forward path includes a differentiator.
According to another aspect of the invention, an audio circuit comprises a fourth order delta-sigma modulator having a feed-forward path connected from an input signal section to the signal path prior to a final integration stage. In one embodiment of the audio circuit, the feed-forward path includes a differentiator. In another embodiment, wherein the modulator comprises a plurality of integrators, at least one of the integrators has a ratio of gain bandwidth product to sampling frequency of less than about 0.2 times a resolution of the modulator. | {
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In various applications using sealing materials for semiconductor LSIs and the like, various resin compounds prepared by mixing an inorganic filler with a resin have been used and proposed.
Nowadays, inorganic fillers having a variety of compositions, average particle diameters, powder properties, and electrical properties are generally used for mixing with resins.
If a filler is added to a resin having high fluidity, an increased amount of the filler added typically decreases the fluidity of the resin compound after finishing adding of the filler, even the particle diameter of the filler or the viscosity of the resin influences. In contrast, if the particle diameter of the filler is large, an increase in the amount of the filler added does not always decrease fluidity. So, a plurality of fillers including a filler mainly for achievement of performance and a filler for control of the fluidity of the resin compound are added in many case.
Examples of the filler mainly for achievement of performance include various powders of metals and/or metal oxides. Examples of the filler for fluidity control include silica powders and carbon black.
In some cases, fillers including silica powders having same composition and different particle diameters having a wide particle size distribution may be used to achieve control of the fluidity of a resin compound. Further, the controlled fluidity and improvement of the filler content may be achieved by the filler such as an irregularly-shaped ferrite powder by making the particle size distribution wide.
A filler is selected depending on the intended application. If a magnetic filler is used for an electromagnetic wave absorption, it is difficult to achieve both a high filler content and a high volume resistivity because control of the various powder properties (such as the average particle diameter, particle size distribution, and shape) of the magnetic filler and adjustment of electrical properties is necessary.
Application using many ferrite powders as magnetic fillers have been proposed. For example, Patent Document 1 (Japanese Patent Laid-Open No. 5-335121) discloses a magnetic sealing material made of a resin containing a ferrite powder surface-treated with a silane coupling agent. It is stated that the magnetic sealing material provides an increased strength and good mold releasability.
Patent Document 2 (Japanese Patent Laid-Open No. 2005-139050) discloses a spherical magnetic ferrite powder having a volume specific resistivity of 5×107 Ωm (5×109 Ωcm) or more at 120° C. and a volume specific resistivity of 3×109 Ωm (3×1011 Ωcm) or more at 25° C. In addition, Patent Document 2 further discloses a resin compound for semiconductor sealing that contains the magnetic ferrite powder which is used together with a silica particle.
Patent Document 2 states that the magnetic ferrite powder disclosed has electromagnetic wave shielding ability and electrical insulating properties, and further, the resin compound for semiconductor sealing which contains the magnetic ferrite powder is highly reliable.
Patent Document 3 (Japanese Patent Laid-Open No. 2005-347449) discloses a soft magnetic powder having a frequency particle size distribution in which a maximum value A exists in the range from 10 μm to 50 μm and a minimum value B exists in the range from 0.5 μm to 10 μm (exclusive of 10 μm); and an organic material prepared by blending the soft magnetic powder with a resin or rubber. Patent Document 3 states that a molded product excellent in electromagnetic wave absorption and heat radiation should be manufactured.
However, the magnetic powders disclosed in Patent Documents 1 to 3 are not the magnetic powder that are good in filling ability if used as a filler, are not excellent in handling properties, and are not high in resistivity prepared even if various powder properties (such as the average particle diameter, particle size distribution, and shape) and electrical properties are adjusted.
Patent Document 4 (Japanese National Publication of International Application NO. 2007/108437) discloses a silica powder at least characterized in that the maximum frequency value for the mode peak 1 present in the particle size range from 1 to 4 μm and a maximum frequency value for the mode peak 2 present in the particle size range from 15 to 55 μm observed in the volume frequency particle size distribution determined by a laser diffraction-scattering method. Wherein, the maximum frequency value for the mode peak 2 is greater than that for the mode peak 1; the mode peak 2 has a shoulder; and the content of particles having particle size range of 15 to 55 μm is greater than the particles having particle size range of 1 to 4 μm. It is also stated that the composition including the silica powder blended with at least either one of rubber or resin is used as a semiconductor-sealing material.
Patent Document 4 states that a sealing material filled with a high content of silica powder which has good moldability, and is less in burr generation should be manufactured. However, Patent Document 4 relates to a silica powder used as a filler for fluidity control and does not relate to a ferrite powder used as a filler for achievement of performance. | {
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Cellular Computer Systems
Modern, high performance, computer systems typically incorporate multiple processors. It is known that some computer systems may embody primary processors of multiple instruction set types, multiple processor systems having primary processors of multiple instruction set architectures (ISAs) are known herein as heterogeneous computer systems.
In addition to primary processors, upon which operating system and user programs run, there are typically additional embedded processors of additional types. Embedded processors are typically provided for control of specific hardware devices, such as disk drives, in the system. In a computer system, embedded processors may perform system management functions as monitoring of primary processor voltages and temperatures, control of cooling subsystems, as well as boot-time configuration of various system components.
A family of high performance heterogeneous computer systems from Hewlett-Packard is capable of being configured to use primary processors of two or more types, including the Intel Itanium and PA8800 instruction set architectures.
In this family of computer systems, a field replaceable “cell” has several primary processor circuits of the same type, together with memory, circuitry for communicating with other cells over a backplane bus, input output (I/O) bus interface circuitry, JTAG (Joint Test Action Group) scan circuitry, and other circuitry. There may be one or more additional embedded processors in each cell to perform system management functions.
One or more cells, which may but need not be of the same type, are installed into a backplane. A heterogeneous computer system is formed when cells having more than one type of processors are inserted into the backplane; a homogeneous computer system is formed if all cells have processors of the same type.
This family of computer systems supports simultaneous execution of multiple operating systems, including multiprocessor versions of Windows-NT, Unix, VMS, and Linux. Multiple instances of each system are also supported. Each operating system instance operates in a partition of a computer system.
At system boot time, a set of processors of a particular type are assigned to operate in each partition. These processors may belong to more than one cell, but must all be of the same ISA. As each operating system boots, or reinitializes, these processors become aware of each other and appropriate task routing and assignment datastructures built in system memory, a process known herein as a Rendezvous of these processors.
During Rendezvous, a processor of each cell is designated a master processor for that cell. One cell of each partition is designated as the master cell for the partition.
Firmware
Most computer systems, including cellular computer systems, have firmware that executes at boot time on each processor. This firmware is responsible for performing self testing, for conducting interprocessor communications including those involved in the Rendezvous and loading the operating system. Firmware is particularly responsible for boot-time operation, once an operating system is loaded some firmware functions may be replaced by related operating system functions.
Error Detection and Handling
Firmware of such computer systems is generally capable of detecting errors that may arise from many causes. As an example, these causes may include problems detected during self-test, interprocessor communication problems, attempts to load incompatible code, rendezvous with processors of an incompatible instruction set architecture, and other errors. Cellular computer systems often recognize multiple errors from single causes, for example corrupt interprocessor communications can be recognized by each of the processors involved.
Many computer systems have firmware capable of handling single errors.
A common method of error reporting is the return-value mechanism. With this mechanism, each subroutine capable of detecting an error returns either zero or an error flag in a register.
Many routines in Unix and similar operating systems combine a single-flag version of the return-value mechanism with an error code stored in a known location. This error code, or ERRNO, can be read by a calling program to obtain some stored information about an error.
Both the return-value mechanism and its ERRNO enhancement are capable of passing only limited information about an error.
In a large, multicellular, computer system, it is desirable to provide the ability to flexibly handle multiple errors. It is desirable to pass sufficient information about an error to other firmware components to permit proper diagnosis and, if possible, automatic recovery from the error. It is also desirable to automatically handle and recover from many potential errors so that at least partial system operation may continue. | {
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Prosthetic devices are artificial devices used to replace or strengthen a particular part of the human body. Various prosthetic devices are available, such as joint replacement prosthesis, stent prosthesis and vascular graft prosthesis. When implanting a prosthesis, such as a stent prosthesis described in greater detail herein, it is desireable that the prosthesis closely assimilate the characteristics of the tissue or bone that the prosthesis is designed to repair or replace. To this end, many attempts have been made to improve biocompatible and mechanical properties of prosthetic devices. Also, it can be desirable to topically medicate the area where the prosthetic has been implanted.
Percutaneous transluminal coronary angioplasty (PTCA) is a procedure for treating heart disease. A catheter assembly having a balloon portion is introduced percutaneously into the cardiovascular system of a patient via the brachial or femoral artery. The catheter assembly is advanced through the coronary vasculature until the balloon portion is positioned across the occlusive lesion. Once in position across the lesion, the balloon is inflated to a predetermined size to radially compress against the atherosclerotic plaque of the lesion to remodel the vessel wall. The balloon is deflated to a smaller profile to allow the catheter to be withdrawn from the patient's vasculature.
A problem associated with the above procedure includes formation of intimal flaps or torn arterial linings which can collapse and occlude the conduit after develop over several months after the procedure, which may require another angoioplasty procedure or a surgical by-pass operation. To reduce the partial or total occlusion of the artery by the collapse of arterial lining and to reduce the chance of the development of thrombosis and restenosis, an expandable intraluminal prosthesis, one example of which includes a stent, is implanted in the lumen to maintain the vascular patency.
Percutaneous endovascular prosthetic stents were conceived in the late 1970's as a way to prevent both acute occlusion and late restenosis after catheter intervention, but initial clinical results of coronary stenting in 1987 were plagued by high (>20%) acute and subacute thrombosis and were restricted to use as “bailout” for threatened or acute vessel closure. In recent years, stent outcomes have improved progressively with better placement techniques and in 1995, an estimated 700,000 stents were implanted world-wide.
Stents are scaffoldings, usually cylindrical or tubular in shape, which function to physically hold open and, if desired, to expand the wall of the passageway. Typically stents are capable of being compressed for insertion through small cavities via small catheters, and expanded to a larger diameter once at the desired location.
To treat the damaged vasculature tissue and assist prevention of thrombosis and restenosis, there is a need for administrating therapeutic substances to the treatment site. For example, anticoagulants, antiplatelets and cytostatic agents are commonly used to prevent thrombosis of the coronary lumen, to inhibit development of restenosis, and to reduce post-angioplasty proliferation of the vascular tissue, respectively. To provide an efficacious concentration to the treated site, systemic administration of such medication often produces adverse or toxic side effects for the patient. Local delivery can be a preferred method of treatment in that smaller total levels of medication are administered at a specific site in comparison to larger overall dosages that are applied systemically. Local delivery produces fewer side effects and achieves more effective results.
One commonly applied technique for the local delivery of a drug is through the use of a polymeric carrier coated onto the surface of a stent by applying to a stent body a solution which includes a specified solvent, a specified polymer dissolved in the solvent, and a therapeutic substance dispersed in the blend. The solvent is allowed to evaporate, leaving on the stent surface a coating of the polymer and the therapeutic substance impregnated in the polymer.
Stents sometimes have to be immersed in a coating solution 12 to 15 times or sprayed 20 times to achieve a satisfactory coating. The immersion method of coating a stent, also called dip-coating, entails submerging the entire stent, or an entire section of the stent, in a coating solution. Similarly, spray-coating requires enveloping the entire stent, or an entire section of the stent, in a large cloud of coating material. Disadvantages of dip-coating and spray-coating methods include the inability to control the exact portions of the stent that come in contact with the coating. Another shortcoming of both dip- and spray-coating is the possibility of forming web-like defects by build-up of excess coating material between the stent struts. Web-like defects are most prevalent in stents having tight patterns, for example coronary stents, such that the distance between the struts is very small.
Each of the methods and devices intended for use just prior to implantation, listed above, deposit the coating material onto any and all surfaces that are exposed to the coating. This may result in depositing coating material on surfaces on which the coating is unwanted or undesirable. Further, the coating may crack or break away when the implantable is removed from the implantation apparatus. An example of this would be a stent deployed on a catheter balloon. As the balloon is inflated and the stent is expanded into position, the coating may crack along the interface between the stent and the balloon. These cracks may lead to a breaking away of a portion of the coating from the stent itself. This, in turn, may affect the medicinal effectiveness of the coating, and negatively affect the entire medical procedure.
Another disadvantage of both dip-coating and spray-coating stems from a low-viscosity requirement for the polymer solution in which the stent is dipped or with which the stent is sprayed. A low viscosity coating solution typically require using a low molecular weight carrier or by using a very low concentration of carrier in the coating solution. Thus, both dip-coating and spray-coating methods have imposed limitations in type and concentration of applied carriers.
Accordingly, it is desirable to provide an improved method of applying a coating to a prosthesis. Specifically, it is desirable to provide a method of applying a polymeric coating to a prosthesis which enables control over the portion of the prosthesis which are coated, reduces the incidence of web-like defects due to excess build-up of polymeric material, broadens the field of both the types and the concentrations of carriers which may be used to coat a prosthesis, and allows a prosthesis to be coated with a polymer and a drug at the same time.
The significance of delivering drug-loaded prostheses may offer savings benefit in time and cost. Studies have been conducted to show the importance of delivering the correct drug dose density on coronary stents to prevent restenosis by application of paclitaxel or rapamycin. Kandazari, David E. et al., Highlights from American Heart Association Annual Scientific Sessions 2001: Nov. 11 to 14, 2001, American Heart Journal 143 (2), 217-228, 2002; Hiatt, Bonnie L. et al., Drug-Eluting Stents for Prevention of Restenosis: In Quest for the Holy Grail, Catheterization and Cardiovascular Interventions 55:409-417, 2002; Kalinowski, M. et al., Paclitaxel Inhibits Proliferation Of Cell Lines Responsible For Metal Stent Obstruction: Possible Topical Application In Malignant Bile Duct Obstructions, Investigational Radiology 37(7):399-404, 2002. Other studies have shown how accuracy of dose related to cytotoxicity of coating drugs. Liebmann, J. E .et al., Cytotoxic Studies Of Paclitaxel (Taxol) In Human Tumor Cell Lines, Br. J. Cancer, 68(6):1104-9, 1993; Adler, L. M. et al., Analysis Of Exposure Times And Dose Escalation Of Paclitaxel In Ovarian Cancer Cell Lines, Cancer, 74(7):1891-8, 1994; Regar, E. et al., Stent Development And Local Drug Delivery, Br. Med. Bulletin, 59:227-48, 2001. See also http://www.tctmd.com/expert-presentations: Farb, A., Comparative Pathology Of Drug Eluting Stents: Insights Into Effectiveness And Toxicity From Animal Lab, CRF Drug-Eluting Stent Symposium 2002; Grube, E., Taxol-Eluting Stent Trials, ISET 2002 Miami Beach, Mar. 19-23, 2002 (The effect of taxol on the edges of the stent and dose response screening); Carter, Andrew J., Sirolimus: Pre-Clinical Studies—Evaluation Of Dosing, Efficacy And Toxicity, TCT September 2001.
Accordingly, the desired features of the invention comprise an apparatus and method for coating a prosthesis which avoid the disadvantages of dip-coating and spray coating methods. In addition, coating the prosthesis can be achieved with such control such that the prosthesis can be coated in the operating room prior to insertion of the prosthesis into the patient, thus avoiding coating portions of the prosthesis or prosthesis handling apparatus, such as a catheter, where such a coating is not desirable.
This is achieved by using contact printing techniques which take advantage of known methods of lithography using self-assembled monolayers. Coating desired portions of the prosthesis can be achieved by stamping the prosthesis with a coating that can form a self-assembled monolayer. The surface of the applicator is coated or saturated with the coating and the applicator is placed in contact with the surface of the prosthesis to be coated to transfer the coating from the applicator to the prosthesis surface.
To form a pattern on a arcuate or curved prosthesis surface, including but not limited to a cylindrical surface, the prosthesis can be rolled over a planar applicator or the prosthesis can be rolled over a curved | {
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1. Field of the Invention
This invention relates to the field of current-carrying devices and components. In particular, the invention relates to a current-carrying device including a substrate and a conductive layer.
2. Description of the Related Art
Current-carrying structures are generally fabricated by subjecting a substrate to a series of manufacturing steps. Examples of such current-carrying structures include printed circuit boards, printed wiring boards, backplanes, and other micro-electronic types of circuitry. The substrate is typically a rigid, insulative material such as epoxy-impregnated glass fiber laminate. A conductive material, such as copper, is patterned to define conductors, including ground and power planes.
Some prior art current-carrying devices are manufactured by layering a conductive material over a substrate. A mask layer is deposited on the conductive layer, exposed, and developed. The resulting pattern exposes select regions where conductive material is to be removed from the substrate. The conductive layer is removed from the select regions by etching. The mask layer is subsequently removed, leaving a patterned layer of the conductive material on the surface of the substrate. In other prior art processes, an electroless process is used to deposit conductive lines and pads on a substrate. A plating solution is applied to enable conductive material to adhere to the substrate on selected portions of the substrate to form patterns of conductive lines and pads.
To maximize available circuitry in a limited footprint, substrate devices sometimes employ multiple substrates, or use both surfaces of one substrate to include componentry and circuitry. The result in either case is that multiple substrate surfaces in one device need to be interconnected to establish electrical communication between components on different substrate surfaces. In some devices, sleeves or vias provided with conductive layering extend through the substrate to connect the multiple surfaces. In multi-substrate devices, such vias extend through at least one substrate to interconnect one surface of that substrate to a surface of another substrate. In this way, an electrical link is established between electrical components and circuitry on two surfaces of the same substrate, or on surfaces of different substrates.
In some processes, via surfaces are plated by first depositing a seed layer of a conductive material followed by an electrolytic process. In other processes, adhesives are used to attach conductive material to via surfaces. In these devices, the bond between the vias and conductive material is mechanical in nature.
Certain materials, referred to below as voltage switchable dielectric materials, have been used in prior art devices to provide over-voltage protection. Because of their electrical resistance properties, these materials are used to dissipate voltage surges from, for example, lightning, static discharge, or power surges. Accordingly, voltage switchable dielectric materials are included in some devices, such as printed circuit boards. In these devices, a voltage switchable dielectric material is inserted between conductive elements and the substrate to provide over-voltage protection. | {
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1. Field of the Invention
This invention relates generally to wireless and long distance carriers, Internet service providers (ISPs), and information content delivery services/providers and long distance carriers. More particularly, it relates to location services for the wireless industry.
2. Background of Related Art
It is desired to accurately locate cell phones within a cellular network. While there are several techniques for determining location in a mobile device, a future generation of mobile phones may include a global positioning satellite (GPS) receiver chipset, thus having the ability to locate itself via GPS.
FIG. 12 depicts the conventional Global Positioning Satellite system including about 24 or more GPS satellites.
In particular, as shown in FIG. 12, the earth 200 is surrounded by approximately 24 GPS satellites 101-124, which each have their own rotational orbit about the earth 200. There are currently about 24 to 27 GPS satellites in the GPS network, each moving about the earth approximately 6 times each day.
Unfortunately, as the phone moves about the country, locations with respect to satellites change. Thus, GPS devices attempting to determine their position with respect to the earth 200 will only be able to communicate with a smaller number of the total GPS satellites at any one time.
The time required for lock in and location determination by a conventional GPS receiver in determining which of the GPS satellites in the GPS network takes several minutes, and as many as 5 or 6 minutes for a standard GPS receiver, which is longer than many if not most phone calls.
There is a need for a less cumbersome and more efficient technique for using GPS location information in a highly mobile and fast paced society. | {
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1. Field of the Invention
The present invention relates generally to the manufacture of chewing gums containing active ingredients and, more specifically, to a method for manufacture of such chewing gums that preserves the efficacy of the active ingredient(s).
2. Description of the Background
The conventional methods of producing compressible chewing gums entail freezing the gum base and then grinding to obtain a particulate material, mixing the particulate material with other materials (usually in particulate form), then pressing the compressible chewing gum mixture into tablets.
For example, U.S. Pat. No. 4,370,350 to Fisher et al. (Wrigley) issued Jan. 25, 1983 shows a method for the manufacture of chewing gum in which the viscosity of the gum base is first reduced by heating. A bulking agent is then added to the gum base while mixing. The mixture is cooled during mixing to form granules. More bulking agent is added to form layers around the granules, and there is no active ingredient nor any grinding or tableting.
For example, U.S. Pat. No. 7,101,579 to Athanikar et al. (Deseret Labs) issued Sep. 5, 2006 shows a chewing gum composition containing an active ingredient. The gum base is cooled to a temperature at which the composition is brittle, ground, mixed with the active ingredient as desired, and formed into a tablet.
U.S. Pat. No. 5,711,961 to Reiner et al. (APR Applied Pharma) issued Jan. 27, 1998 discloses a pharmaceutical chewing gum composition in tablet form made by freezing, grinding the gum in a mill, and granulating the ground gum in a fluid bed. Thereafter, a medicinal active agent is mixed with the granulate, and the granulates are compressed into tablets. This patent is provided for general interest.
U.S. Pat. No. 4,975,270 to Kehoe (Nabisco) issued 4 Dec. 1990 shows a medicament-active chewing gum made by freezing and grinding into a particle. Note that the gum and the active ingredient are mixed together while heating, and then the mixture is frozen and ground into particles.
U.S. Pat. No. 6,582,738 to Gubler (Deseret Laboratories) issued Jun. 24, 2003 shows a process for preparing chewing gum containing a nutritional supplement that includes cooling and grinding the cooled, brittle gum composition to form a chewing gum powder, mixing with an active nutritional supplement, granulating, and then compressing the granules to form chewing gum tablets. The chewing gum composition is cooled to a temperature at which the gum composition is brittle.
Alternatively it is known to mix a powder sweetener into a molten gum base while subjecting the mixture to shear (i.e., through the mixing force) and cooling. This technique causes the grinding as the mixture becomes more rigid due to cooling and the addition of the dry sweetener.
U.S. Pat. No. 4,753,805 to Cherukuri et al. (Warner-Lambert) issued Jun. 28, 1988 shows a tabletted chewing gum composition and method of preparation in which a gum base is mixed with a sweetener, and the mixture is ground with an abrasive grinding aid (alkali metal phosphates, alkaline earth metal phosphates, maltodextrins).
U.S. Pat. No. 7,208,186 (SPI Pharma, Inc.) to Norman et al. issued Apr. 24, 2007 shows a chewing gum formulation with an active ingredient. The gum base, granulating agent and a processing aid are mixed until in particulate form. The temperature in the mixer is then increased to a temperature which is sufficient to melt at least the surface of the gum base particles and the contents of the mixer are mixed for several minutes at this temperature to obtain a uniform mixture of the gum base, the granulating agent and the processing aid in particulate form particles inside the mixer. Next, the active ingredient is added to the particles and most or all of the active ingredient is loosely bound to the outer surfaces of the particles. The particles are tableted. There is no cooling necessary to make the chewing gum formulation friable.
U.S. Pat. No. 7,351,438 to Sozzi et al. (Gum Base Co., SPA) issued Apr. 1, 2008 shows a method of preparing chewing gum in tablet form by direct compression of the chewing gum formulation in powder form. The chewing gum in powder form is produced by a method which comprises the following steps:
a) mixing of a soft basic gum with at least one sweetener and, optionally, at least one other typical chewing-gum ingredient, at a temperature of between 35 and 75° C.,
b) cooling of the mixture thus obtained to a temperature of between 0 and −40° C. and preferably between −10 and −40° C.,
c) grinding and subsequent screening of the mixture thus obtained to a particle size of less than 10 mesh,
d) optional mixing of the powder thus obtained with at least one anti-agglutination agent,
e) optional compression of the mixture thus obtained.
U.S. Pat. No. 5,866,179 to Testa (Avant-Garde Technologies) issued Feb. 2, 1999 shows a medicated chewing gum and a process for preparation thereof in which the active agent is mixed with a granulated gum base under controlled temperature and humidity and the blended components are cold-pressed to produce a final gum product. The gum base is prepared by cooling natural gum to −10 degree C., then grinding it. It is noted that the elevated temperatures used in the melt can adversely affect the chemical stability of the therapeutic agent.
Neither prior method is optimal for chewing gums with active ingredients since heating and/or cooling can erode the effectiveness of the active. The proposed process avoids this by initially heating a gum base to slightly elevated internally measured temperature between 140-160 deg. F. in ovens, mixing with the active as it cools to produce a particulate mixture, grinding into compressible powder, then forming into tablets. The temperature of the gum base exceeds that of the mixer when first introduced, but as mixing continues it cools and mixes into a particulate form=inside the mixer. Next, the particulate is ground into compressible powder at room temperature, mixed at room temperature with excipients, and tableted. This avoids heating/cooling of the active and preserves its efficacy. | {
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The hepatitis C virus (HCV) is the leading cause of chronic liver disease worldwide. (Boyer, N. et al. J. Hepatol. 32:98-112, 2000). HCV causes a slow growing viral infection and is the major cause of cirrhosis and hepatocellular carcinoma (Di Besceglie, A. M. and Bacon, B. R., Scientific American, Oct.: 80-85, (1999); Boyer, N. et al. J. Hepatol. 32:98-112, 2000). An estimated 170 million persons are infected with HCV worldwide. (Boyer, N. et al. J. Hepatol. 32:98-112, 2000). Cirrhosis caused by chronic hepatitis C infection accounts for 8,000-12,000 deaths per year in the United States, and HCV infection is the leading indication for liver transplant.
HCV is known to cause at least 80% of posttransfusion hepatitis and a substantial proportion of sporadic acute hepatitis. Preliminary evidence also implicates HCV in many cases of “idiopathic” chronic hepatitis, “cryptogenic” cirrhosis, and probably hepatocellular carcinoma unrelated to other hepatitis viruses, such as Hepatitis B Virus (HBV). A small proportion of healthy persons appear to be chronic HCV carriers, varying with geography and other epidemiological factors. The numbers may substantially exceed those for HBV, though information is still preliminary; how many of these persons have subclinical chronic liver disease is unclear. (The Merck Manual, ch. 69, p. 901, 16th ed., (1992)).
HCV has been classified as a member of the virus family Flaviviridae that includes the genera flaviviruses, pestiviruses, and hapaceiviruses which includes hepatitis C viruses (Rice, C. M., Flaviviridae: The viruses and their replication. In: Fields Virology, Editors: Fields, B. N., Knipe, D. M., and Howley, P. M., Lippincott-Raven Publishers, Philadelphia, Pa., Chapter 30, 931-959, 1996). HCV is an enveloped virus containing a positive-sense single-stranded RNA genome of approximately 9.4 kb. The viral genome consists of a 5′ untranslated region (UTR), a long open reading frame encoding a polyprotein precursor of approximately 3011 amino acids, and a short 3′ UTR. The 5′ UTR is the most highly conserved part of the HCV genome and is important for the initiation and control of polyprotein translation. Translation of the HCV genome is initiated by a cap-independent mechanism known as internal ribosome entry. This mechanism involves the binding of ribosomes to an RNA sequence known as the internal ribosome entry site (IRES). An RNA pseudoknot structure has recently been determined to be an essential structural element of the HCV IRES. Viral structural proteins include a nucleocapsid core protein (C) and two envelope glycoproteins, E1 and E2. HCV also encodes two proteinases, a zinc-dependent metalloproteinase encoded by the NS2-NS3 region and a serine proteinase encoded in the NS3 region. These proteinases are required for cleavage of specific regions of the precursor polyprotein into mature peptides. The carboxyl half of nonstructural protein 5, NS5B, contains the RNA-dependent RNA polymerase. The function of the remaining nonstructural proteins, NS4A and NS4B, and that of NS5A (the amino-terminal half of nonstructural protein 5) remain unknown.
A significant focus of current antiviral research is directed toward the development of improved methods of treatment of chronic HCV infections in humans (Di Besceglie, A. M. and Bacon, B. R., Scientific American, Oct.: 80-85, (1999)). Currently, there are two primary antiviral compounds, Ribavirin and interferon-alpha, which are used for the treatment of chronic HCV infections in humans.
Treatment of HCV Infection with Ribivarin
Ribavirin (1-β-D-ribofuranosyl-1-1,2,4-triazole-3-carboxamide) is a synthetic, non-interferon-inducing, broad spectrum antiviral nucleoside analog sold under the trade name, Virazole (The Merck Index, 11th edition, Editor: Budavari, S., Merck & Co., Inc., Rahway, N.J., p 1304, 1989). U.S. Pat. Nos. 3,798,209 and RE29,835 disclose and claim Ribavirin. Ribavirin is structurally similar to guanosine, and has in vitro activity against several DNA and RNA viruses including Flaviviridae (Gary L. Davis. Gastroenterology 118:S104-S114, 2000).
Ribavirin reduces serum amino transferase levels to normal in 40% or patients, but it does not lower serum levels of HCV-RNA (Gary L. Davis. Gastroenterology 118:S104-S114, 2000). Thus, Ribavirin alone is not effective in reducing viral RNA levels. Additionally, Ribavirin has significant toxicity and is known to induce anemia.
Treatment of HCV Infection with Interferon
Interferons (IFNs) are compounds that have been commercially available for the treatment of chronic hepatitis for nearly a decade. IFNs are glycoproteins produced by immune cells in response to viral infection. IFNs inhibit viral replication of many viruses, including HCV, and when used as the sole treatment for hepatitis C infection, IFN suppresses serum HCV-RNA to undetectable levels. Additionally, IFN normalizes serum amino transferase levels. Unfortunately, the effects of IFN are temporary and a sustained response occurs in only 8%-9% of patients chronically infected with HCV (Gary L. Davis. Gastroenterology 118:S104-S114, 2000).
A number of patents disclose HCV treatments using interferon-based therapies. For example, U.S. Pat. No. 5,980,884 to Blatt et al. discloses methods for retreatment of patients afflicted with HCV using consensus interferon. U.S. Pat. No. 5,942,223 to Bazer et al. discloses an anti-HCV therapy using ovine or bovine interferon-tau. U.S. Pat. No. 5,928,636 to Alber et al. discloses the combination therapy of interleukin-12 and interferon alpha for the treatment of infectious diseases including HCV. U.S. Pat. No. 5,908,621 to Glue et al. discloses the use of polyethylene glycol modified interferon for the treatment of HCV. U.S. Pat. No. 5,849,696 to Chretien et al. discloses the use of thymosins, alone or in combination with interferon, for treating HCV. U.S. Pat. No. 5,830,455 to Valtuena et al. discloses a combination HCV therapy employing interferon and a free radical scavenger. U.S. Pat. No. 5,738,845 to Imakawa discloses the use of human interferon tau proteins for treating HCV. Other interferon-based treatments for HCV are disclosed in U.S. Pat. No. 5,676,942 to Testa et al, U.S. Pat. No. 5,372,808 to Blatt et al., and U.S. Pat. No. 5,849,696.
Combination of Interferon and Ribavirin
The combination of IFN and Ribavirin for the treatment of HCV infection has been reported to be effective in the treatment of IFN naive patients (Battaglia, A. M. et al., Ann. Pharmacother. 34:487-494, 2000). Results are promising for this combination treatment both before hepatitis develops or when histological disease is present (Berenguer, M. et al. Antivir. Ther. 3(Suppl. 3):125-136, 1998). Side effects of combination therapy include hemolysis, flu-like symptoms, anemia, and fatigue. (Gary L. Davis. Gastroenterology 118:S104-S114, 2000).
Additional References Disclosing Methods to Treat HCV Infections
A number of HCV treatments are reviewed by Bymock et al. in Antiviral Chemistry & Chemotherapy, 11:2; 79-95 (2000).
Several substrate-based NS3 protease inhibitors have been identified in the literature, in which the scissile amide bond of a cleaved substrate is replaced by an electrophile, which interacts with the catalytic serine. Attwood et al. (1998) Antiviral peptide derivatives, 98/22496; Attwood et al. (1999), Antiviral Chemistry and Chemotherapy 10.259-273; Attwood et al. (1999) Preparation and use of amino acid derivatives as anti-viral agents, German Patent Publication DE 19914474; Tung et al. (1998) Inhibitors of serine proteases, particularly hepatitis C virus NS3 protease, WO 98/17679. The reported inhibitors terminate in an electrophile such as a boronic acid or phosphonate. Llinas-Brunet et al. (1999) Hepatitis C inhibitor peptide analogues, WO 99/07734. Two classes of electrophile-based inhibitors have been described, alphaketoamides and hydrazinoureas.
The literature has also described a number of non-substrate-based inhibitors. For example, evaluation of the inhibitory effects of 2,4,6-trihydroxy-3-nitro-benzamide derivatives against HCV protease and other serine proteases has been reported. Sudo, K. et al., (1997) Biochemical and Biophysical Research Communications, 238:643-647; Sudo, K. et al. (1998) Antiviral Chemistry and Chemotherapy 9:186. Using a reverse-phase HPLC assay, the two most potent compounds identified were RD3-4082 and RD3-4078, the former substituted on the amide with a 14 carbon chain and the latter processing a para-phenoxyphenyl group.
Thiazolidine derivatives have been identified as micromolar inhibitors, using a reverse-phase HPLC assay with an NS3/4A fusion protein and NS5A/5B substrate. Sudo, K. et al. (1996) Antiviral Research 32:9-18. Compound RD-1-6250, possessing a fused cinnamoyl moiety substituted with a long alkyl chain, was the most potent against the isolated enzyme. Two other active examples were RD4 6205 and RD4 6193.
Other literature reports screening of a relatively small library using an ELISA assay and the identification of three compounds as potent inhibitors, a thiazolidine and two benzanilides. Kakiuchi N. et al. J. EBS Letters 421:217-220; Takeshita N. et al., Analytical Biochemistry 247:242-246, 1997. Several U.S. patents disclose protease inhibitors for the treatment of HCV. For example, U.S. Pat. No. 6,004,933 to Spruce et al. discloses a class of cysteine protease inhibitors for inhibiting HCV endopeptidase 2. U.S. Pat. No. 5,990,276 to Zhang et al. discloses synthetic inhibitors of hepatitis C virus NS3 protease. The inhibitor is a subsequence of a substrate of the NS3 protease or a substrate of the NS4A cofactor. The use of restriction enzymes to treat HCV is disclosed in U.S. Pat. No. 5,538,865 to Reyes et al.
Isolated from the fermentation culture broth of Streptomyces sp., Sch 68631, a phenan-threnequinone, possessed micromolar activity against HCV protease in a SDS-PAGE and autoradiography assay. Chu M. et al., Tetrahedron Letters 37:7229-7232, 1996. In another example by the same authors, Sch 351633, isolated from the fungus Penicillium griscofuluum, demonstrated micromolar activity in a scintillation proximity assay. Chu M. et al., Bioorganic and Medicinal Chemistry Letters 9:1949-1952. Nanomolar potency against the HCV NS3 protease enzyme has been achieved by the design of selective inhibitors based on the macromolecule eglin c. Eglin c, isolated from leech, is a potent inhibitor of several serine proteases such as S. griseus proteases A and B, α-chymotrypsin, chymase and subtilisin. Qasim M. A. et al., Biochemistry 36:1598-1607, 1997.
HCV helicase inhibitors have also been reported. U.S. Pat. No. 5,633,358 to Diana G. D. et al.; PCT Publication No. WO 97/36554 of Diana G. D. et al. There are a few reports of HCV polymerase inhibitors: some nucleotide analogues, gliotoxin and the natural product cerulenin. Ferrari R. et al., Journal of Virology 73:1649-1654, 1999; Lohmann V. et al., Virology 249:108-118, 1998.
Antisense phosphorothioate oligodeoxynucleotides complementary to sequence stretches in the 5′ non-coding region of the HCV, are reported as efficient inhibitors of HCV gene expression in in vitro translation and IIcpG2 IICV-luciferase cell culture systems. Alt M. et al., Hepatology 22:707-717, 1995. Recent work has demonstrated that nucleotides 326-348 comprising the 3′ end of the NCR and nucleotides 371-388 located in the core coding region of the HCV RNA are effective targets for antisense-mediated inhibition of viral translation. Alt M. et al., Archives of Virology 142:589-599, 1997. U.S. Pat. No. 6,001,990 to Wands et al. discloses oligonucleotides for inhibiting the replication of HCV. PCT Publication No. WO 99/29350 discloses compositions and methods of treatment for hepatitis C infection comprising the administration of antisense oligonucleotides that are complementary and hybridizable to HCV-RNA. U.S. Pat. No. 5,922,857 to Han et al. disclose nucleic acids corresponding to the sequence of the pestivirus homology box IV area for controlling the translation of HCV. Antisense oligonucleotides as therapeutic agents have been recently reviewed (Galderisi U. et al., Journal of Cellular Physiology 181:251-257, 1999).
Other compounds have been reported as inhibitors of IRES-dependent translation in HCV. Japanese Patent Publication JP-08268890 of Ikeda N et al.; Japanese Patent Publication JP-10101591 of Kai, Y. et al. Nuclease-resistant ribozymes have been targeted at the IRES and recently reported as inhibitors in an HCV-poliovirus chimera plaque assay. Maccjak D. J. et al., Hepatology 30 abstract 995, 1999. The use of ribozymes to treat HCV is also disclosed in U.S. Pat. No. 6,043,077 to Barber et al., and U.S. Pat. Nos. 5,869,253 and 5,610,054 to Draper et al.
Other patents disclose the use of immune system potentiating compounds for the treatment of HCV. For example, U.S. Pat. No. 6,001,799 to Chretien et al. discloses a method of treating hepatitis C in non-responders to interferon treatment by administering an immune system potentiating dose of thymosin or a thymosin fragment. U.S. Pat. Nos. 5,972,347 to Eder et al. and 5,969,109 to Bona et al. disclose antibody-based treatments for treating HCV.
U.S. Pat. No. 6,034,134 to Gold et al. discloses certain NMDA receptor agonists having immunodulatory, antimalarial, anti-Borna virus and anti-Hepatitis C activities. The disclosed NMDA receptor agonists belong to a family of 1-amino-alkylcyclohexanes. U.S. Pat. No. 6,030,960 to Morris-Natscke et al. discloses the use of certain alkyl lipids to inhibit the production of hepatitis-induced antigens, including those produced by the HCV virus. U.S. Pat. No. 5,922,757 to Chojkier et al. discloses the use of vitamin E and other antioxidants to treat hepatic disorders including HCV. U.S. Pat. No. 5,858,389 to Elsherbi et al., discloses the use of squalene for treating hepatitis C. U.S. Pat. No. 5,849,800 to Smith et al discloses the use of amantadine for treatment of Hepatitis C. U.S. Pat. No. 5,846,964 to Ozeki et al. discloses the use of bile acids for treating HCV. U.S. Pat. No. 5,491,135 to Blough et al. discloses the use of N-(phosphonoacetyl)-L-aspartic acid to treat flaviviruses such as HCV.
Other compounds proposed for treating HCV include plant extracts (U.S. Pat. No. 5,837,257 to Tsai et al., U.S. Pat. No. 5,725,859 to Omer et al., and U.S. Pat. No. 6,056,961), piperidenes (U.S. Pat. No. 5,830,905 to Diana et al.), benzenedicarboxamides (U.S. Pat. No. 5,633,388 to Diana et al.), polyadenylic acid derivatives (U.S. Pat. No. 5,496,546 to Wang et al.), 2′,3′-dideoxyinosine (U.S. Pat. No. 5,026,687 to Yarchoan et al.), benzimidazoles (U.S. Pat. No. 5,891,874 to Colacino et al.).
In light of the fact that the hepatitis C virus has reached epidemic levels worldwide, and has tragic effects on the infected patient, there remains a strong need to provide new effective pharmaceutical agents to treat hepatitis C that has low toxicity to the host.
Therefore, it is an object of the present invention to provide a compound, method and composition for the treatment of a host infected with hepatitis C virus. | {
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1. Field of the Invention
This invention relates to a system and method of attitude control for flight vehicles including missiles, kill vehicles and space craft.
2. Description of the Related Art
Attitude control systems are used to maneuver flight vehicles such as a missile, kill vehicle (KV) or space craft. One approach is to control moveable fins or other airfoils to produce the force vector required to pitch and yaw the flight vehicle. This approach is relatively inexpensive but is not capable of maneuvering the vehicle with both speed and precision, has moving parts that reduce reliability and will not work in space. Another approach is to use active thrusters. This approach is considerably more expensive and has its own reliability concerns due to the complexity of the thrusters and closed-loop control systems. Active thrusters can produce larger force vectors to reduce the response time of any maneuver.
As shown in FIG. 1, a missile 10 is oriented with its body axis 12 along the x-axis. The missile's rocket motor 14 produces a thrust vector 16 that ordinarily imparts a force on the missile along its body axis. An articulated nozzle 18 turns thrust vector 16 to impart a pitch (rotation about the y-axis) or yaw (rotation about the z-ax) moment to the missile. An IMU 20 measures the attitude of the missile and provides active feedback control to articulated nozzle 18. This is known as “Thrust Vector Control” and is typically used with tactical missiles during flight to provide relatively gross and slow attitude control. A related approach is to fix nozzle 18 but place turning vanes inside the nozzle to turn the thrust vector. This is known as “Jet Vane Control”. Both techniques require moving parts, are relatively expensive solutions and are generally incapable of executing tight turning radius maneuvers.
Another approach is to use a combination of roll-control thrusters and pitch-over thrusters as illustrated in FIGS. 2a-2c and 3a-3c. A pair of roll-control thrusters 30 and 32 are mounted on opposite sides of a missile 34 so that their thrust vectors produce a rotational moment that “rolls” the missile around its body axis in either direction. A pair of pitch-over thrusters 36 and 38 are mounted on opposite sides of missile 34 in the pitch plane and offset from the missile's center of gravity so that their thrust vectors produce a rotational moment that “pitches” the missile. Because the missile's moment of inertia to pitch is much greater than its moment of inertia to roll, the pitch thrusters are generally capable of producing substantially more thrust than are the roll-control thrusters. Both types of thrusters are typically fixed amplitude and variable pulse-width to control the total applied force. Although the roll-control and pitch-over thrusters are shown on the missile orthogonal to each other, they can be aligned or have any desired orientation with respect to each other because they act independently.
To maneuver missile 34 from its current heading to an attitude 40, the roll-control thrusters 30 and 32 and than the pitch-over thrusters 36 and 38 are fired in sequence. Because the “roll” and “pitch” maneuvers are performed sequentially, any error in the “roll” maneuver will induce a large error in the “pitch”. Consequently, active closed-loop control is used for both maneuvers. As shown in FIGS. 2a and 3, roll-control thruster 30 is fired producing thrust vector 42 that rolls the missile in a counter-clockwise direction. In an active closed-loop control system, the IMU will constantly measure the roll angle and feed it back to the attitude controller, which in turn will either continue to fire thruster 30 to continue rolling the missile or, if the missile has rolled to far, fire thruster 32 produces thrust vector 44 to roll it back. Once the roll maneuver has stabilized so that the plane of pitch-over thrusters 36 and 38 is aligned with desired attitude 40, pitch-over thruster 36 is fired producing a thrust vector 46 that rotates the missile around its center of gravity in the pitch plane. The attitude controller actively controls pitch-over thrusters 36 and 38, which produce thrust vectors 46 and 48, to stabilize the orientation of the missile along attitude 40. Although this approach is widely used for attitude control in large, expensive missile systems, the attitude control system is expensive and less reliable on account of the pulse-width modulated thrusters and active control system and relatively slow on account of the sequential “roll” and “pitch” maneuvers.
In modern weapons systems and space craft demands are being placed on the attitude control systems to be able to perform attitude maneuvers very quickly and precisely with high reliability and at low cost. Smaller and lower cost flight vehicles are being planned for deployment in much higher volumes that are placing higher demands on performance at lower costs. The known approaches for attitude control cannot meet the cost-performance requirements of these systems. | {
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Luminous tube signage has been used for decades. Typically, a tortuous length of glass tubing is formed into the desired design. Next, electrodes are sealed to either end, with one electrode being tubulated. The tube is then processed: baked, exhausted, backfilled and sealed. A transformer then applies voltage across the electrodes and causes the gas to give off light
The manufacture of the electrodes is time consuming and labor intensive. FIG. 1 shows a prior art arrangement for manufacturing such electrodes. Typically, an electrode shell 10 includes two conductors 12 attached thereto. The conductors are inserted into die block holes 14. A tungsten mandrel 15 is arranged beneath the tubulations and moves up into the tubulation as described below.
In operation, the entire arrangement of FIG. 1 is spun and heat is introduced in the area labeled 20 where the outer tube and inner tubulation overlap. Once outer tube 22 and inner tubulation 18 are red hot and plastic, the tungsten mandrel moves up inside the tubulation. Immediately thereafter, two press blocks (not shown for clarity) press area 20 inward, forming what is known in the industry as a pinch seal. The mandrel is then removed and the part annealed.
FIG. 1A shows the finished electrode. FIG. 1B is a side view of the finished electrode of FIG. 1A.
The problem lies in the fact that the parts must be loaded by hand. The process of inserting two wires attached to an electrode shell into two holes cannot be automated.
The prior art process for manufacturing electrodes is somewhat automated, but the machines must be manually loaded. Manual loading limits production drastically, and increases "shrinkge"; i.e. broken parts due to operator errors.
For example, the design of a neon electrode necessitates manual loading by an operator. On an 8 head machine, an operator must perform a lengthy sequence of steps including (i) load a tubulation, (ii) insert an electrode shell with its two conductors engaged into two 0.030 diameter holes (iii) load an outer tube, and (iv) remove one finished part. This sequence is typically performed every 12 seconds, constantly, all day. The process produces approximately 300 electrodes per hour, less shrinkage of about 5% for a good operator.
Consider a glass part designed to be mass produced, such as a glass stem for a florescent lamp or a light bulb. These parts are produced without labor on a machine producing approximately 4000 per hour with about 2% shrinkage.
In view of the above, it can be appreciated that there exists a need for an improved design and manufacturing process for luminous tube electrodes which allows full automation and mass production. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to electrical interconnections in integrated circuit structures, and in particular, to a process for forming interconnections between layers of electrically conductive material in integrated circuit structures.
2. Prior Art
Most integrated circuit manufacturing operations have relied upon aluminum or alloys of aluminum with copper or other materials for fabricating the interconnections between regions on the surface of an integrated circuit structure. The technology for fabricating such interconnections using aluminum is well known. Numerous techniques are also known for forming "vias" which are used to connect an underlying conductive layer to an overlying conductive layer otherwise separated by an intervening region of insulating material.
Unfortunately, aluminum interconnections in integrated circuit structures suffer from several disadvantages. Aluminum lines are prone to electromigration as the electric current flowing through the aluminum conductor progressively shifts aluminum atoms from one location to another, eventually causing failure of the connecting line. In addition, aluminum conductors, and many other metals or alloys, form oxides which make creating reliable ohmic connections to the conductor difficult. Further, because aluminum, and alloys of aluminum, melt at relatively low temperatures, subsequent processing of an integrated circuit structure after deposition of aluminum is necessarily limited. To overcome these and other disadvantages of aluminum interconnections, metal silicides are being increasingly studied as an alternative means of providing a high conductivity metallization system in integrated circuit structures. A recent publication indicative of this interest is "Refractory Silicides for Low Resistivity Gates and Interconnects" by S. P. Murarka, Technical Digest of the 1979 International Electron Devices Meeting, Washington, D.C., Dec. 3-5, 1979. | {
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The present invention relates to flower delivery networks. In particular, the invention relates to methods and systems for assuring quality in the delivered product.
Flower arrangements are often sold to a customer at the location of a first florist for delivery to a far distant recipient. To meet this need, networks of florist have arisen so that the first florist, called the sending florist, sends an order to a filling florist at a location near the recipient. Flower arrangements are standardized within the network, and the network management distributes instructions for making each standardized flower arrangement along with a photograph of the finished flower arrangement.
With such a network, a customer comes to the sending florist, chooses one of the standard flower arrangements, and pays the sending florist, leaving delivery instructions for delivery to the distant recipient. Often, a personalized message will accompany the delivery of the flower arrangement. The selection number of the chosen flower arrangement, the delivery address, and the personalized message, if any, along with an order number are sent as an order to the filling florist. The order number is associated the sending and filling florists along with their addresses, telephone numbers, etc. The filling florist makes up the flower arrangement, attaches the personalized message, if any, and delivers the flower arrangement the recipient at the address identified in the order. Upon delivery, the filling florist sends a report, including the order number, of the delivery to the sending florist, and the filling florist is paid a portion of the price originally paid to the sending florist by the original customer. In some instances, the sending florist is an Internet web site that takes orders and functions as the sending florist.
Occasionally, a filling florist may run out of a particular flower and make substitutions in the flower arrangement, simply prepare the flower arrangement with less than the prescribed number of flowers, or use old flowers that had begun to wilt. Should a filling florist frequently make flower arrangements with less than the prescribed number of flowers or use old flowers that had begun to wilt, the filling florist would make a windfall profit. The filling florist may feel a financial motivation to vary from the network management's prescribed instructions for making the standardized flower arrangement.
Eventually, recipients talk to customers, and if the flower arrangement varied from the arrangement ordered, the customer may complain to the sending florist with whom the order was placed. Disputes arise between sending and filling florist, and the value of the whole network concept is questioned.
Quality control of the delivered flower arrangement is an important aspect of the management of the network. In some instances, a filling florist have taken photographs with electronic cameras attached the file created by the camera to an E-mail sent back to the sending florist For example, the file created by the camera may be in a JPEG format for attachment to an E-mail.
However, what is needed is a regular means to ensure quality of the delivered flower arrangement to enhance the value of the network concept to all participating florists. | {
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The increasing demand for electronic devices for application areas such as automotive, smartphones and the Internet of Things (IoT) has resulted in an increased demand for high performance and high reliability integrated circuits. Electronic devices for these application areas are continually moving towards higher functionality and miniaturization of size. As a result, demand is increasing for integrated circuit packaging approaches that are smaller, more compact and more reliable.
One approach that has been developed is Molded Interconnect Substrate (MIS). MIS is a substrate solution that utilizes embedded copper trace technology to meet the demands for high I/O counts and a smaller size or form factor. MIS uses materials that are more compatible with the thermal-mechanical properties of integrated circuit materials such as silicon. For a typical packaging application that uses MIS, an integrated circuit die is attached to a substrate using a wire bond or flip-chip process. The top of the substrate is covered with a molding compound and external contacts for the integrated circuit are provided at a bottom of the substrate. | {
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1. Field of the Invention
Conventionally, a high voltage which is required for program or erasure is generated inside a chip by an internal voltage generation circuit accompanied with the use of a single power supply in a non-volatile semiconductor memory.
2. Description of the Related Art
A voltage limiter circuit (voltage setting circuit) is used in the internal voltage generation circuit, since a power supply voltage supplied from the outside is stepped up by the charge pump circuit and an output voltage of the charge pump circuit is set at a desired voltage value (internal voltage) (see Japanese Patent Application Laid Open No. 11-353889).
The voltage limiter circuit using an R-2R resistance ladder which is a kind of current additional D/A converter has been employed, if it is necessary to set a number of variable voltages in a conventional non-volatile semiconductor memory. The voltage limiter circuit using the R-2R resistance ladder requires two differential amplifiers in a part of the circuit composition. However, the system had the problem that a desired voltage step could not be obtained if offset occurs between the two differential amplifiers themselves due to dispersion in processes or the like. | {
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Electronic devices installed in a vehicle have been increased significantly in their number and variety along with recent digitalization of vehicle parts. Generally, the electronic devices may be used throughout the vehicle, for example, a power train control system (e.g., an engine control system, an automatic transmission control system, or the like), a body control system (e.g., a body electronic equipment control system, a convenience apparatus control system, a lamp control system, or the like), a chassis control system (e.g., a steering apparatus control system, a brake control system, a suspension control system, or the like), a vehicle network (e.g., a controller area network (CAN), a FlexRay-based network, a media oriented system transport (MOST)-based network, or the like), a multimedia system (e.g., a navigation apparatus system, a telematics system, an infotainment system, or the like), and so forth.
The electronic devices used in each of these systems are connected via the vehicle network, which supports functions of the electronic devices. For instance, the CAN may support a transmission rate of up to 1 Mbps and support automatic retransmission of colliding messages, error detection based on a cycle redundancy interface (CRC), or the like. The FlexRay-based network may support a transmission rate of up to 10 Mbps and support simultaneous transmission of data through two channels, synchronous data transmission, or the like. The MOST-based network is a communication network for high-quality multimedia, which may support a transmission rate of up to 150 Mbps.
The telematics system and the infotainment system, as most enhanced safety systems of a vehicle do, require higher transmission rates and system expandability. However, the CAN, FlexRay-based network, and the like may not sufficiently support such requirements. The MOST-based network, in particular, may support a higher transmission rate than the CAN or the FlexRay-based network. However, applying the MOST-based network to vehicle networks can be costly. Due to these limitations, an Ethernet-based network is often utilized as a vehicle network. The Ethernet-based network may support bi-directional communication through one pair of windings and may support a transmission rate of up to 10 Gbps.
In recent years, Ethernet has been applied to the vehicle network, but there is no suggestion of error handling and recovery according to the type and level of a physical error or a logical error. Therefore, there is a need for an Ethernet communication apparatus and a method for error recovery, which can perform error handling and recovery according to the type and level of the physical or logical error that occurs during Ethernet communications. | {
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1. Field of the Invention
The present invention relates to a copying apparatus having an optical scanning imaging system and more particularly to a copying apparatus having a compact erect optical imaging system.
2. Description of the Prior Art
A large number of copying apparatus are known in the prior art and are widely used commercially. Generally, these copying apparatus can vary from a simple wet process copier to complex multiple copy electrostatic copiers. The competitive pressure of a number of entrants into the copying field has increased the efforts to provide more economical machines that ate compact while at the same time maintaining the necessary requirements of image clarity. The optical systems that have been suggested and utilized in the copier field have ranged from conjugate lens systems for reproducing the entire document at one time to lenticular bars used in scanning a relatively moving original object.
One of the known problems in the copier field is the requirement of a relatively long track length between the original object and the copy. The long track length is necessary in order to provide an adequate field of view angle for the imaging objective lens system. Efforts to reduce the track length by increasing the number of lens elements correspondingly increases the cost of the lens system.
In efforts to provide a compact scanning copier apparatus, various suggestions have existed in the patent literature such as the two lenticular screens of U.S. Pat. No. 3,447,438; the pairs of lenslets suggested in U.S. Pat. No. 3,694,076; the overlapping lens strips suggested in U.S. Pat. No. 3,655,284 and the fiber optical imaging system suggested in U.S. Pat. Nos. 3,398,669 and 3,560,084.
Other strip scanning copying apparatus are suggested in U.S. Pat. Nos. 3,580,675, U.S. Pat. No. 3,836,249 and U.S. Pat. No. 3,592,542.
Attempts have been made to provide relatively inexpensive constructions of lens strip imaging devices by duplicating individual lens elements and molding them from plastic or assembling them in an array. Problems of providing the reproduction clarity required while removing vignetting, spherical aberration and field curvature problems and further maintaining a relatively economic imaging lens system has plagued these design efforts to date.
Accordingly, there is a need in the copier field to provide a compact erect optical imaging system that can be manufactured for a relatively low cost while providing minimal distortion and aberrations in the projected image. | {
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1. Field of the Invention
The present invention relates generally to the field of reciprocating engines, and more specifically, to an improved piston with radially-oriented and tapered grooves on the piston head.
2. Description of the Related Art
Most automobile engines are internal combustion engines in which the fuel burns in a plurality of combustion chambers inside of an engine block. Directly beneath each combustion chamber is a cylinder, and most engines have four, six or eight cylinders. A piston moves up and down (reciprocates) inside of each cylinder, and the piston face (or top surface) forms the floor of the combustion chamber. In a typical engine, the number of cylinders equals the number of pistons.
When the air-fuel mixture inside of the combustion chamber ignites, the explosive force pushes the piston downward. Each piston is connected to a crankshaft by a connecting rod. The pistons are configured on the crankshaft such that the downward force of one or more pistons causes one or more other pistons to move upward, thereby compressing the air-fuel mixture inside of the combustion chamber. Each combustion chamber has a port for an intake valve, an exhaust valve, and a spark plug. In a properly functioning engine, the spark plug delivers a spark to the combustion chamber when the piston is nearly at its upward-most position within the combustion chamber during the compression stroke.
A typical engine comprises four “strokes,” which refer to the up-and-down motion of the piston: intake, compression, power and exhaust. During the intake stroke, the piston moves downward as the air-fuel mixture is introduced into the combustion chamber through the intake valve. During the compression stroke, the piston moves upward and compresses the air-fuel mixture. During the power stroke, the air-fuel mixture has ignited, creating the explosive force that drives the piston downward. During the exhaust stroke, the piston moves upward, pushing the exhaust fumes through the exhaust valve.
The present invention is not limited to four-stroke (or four-cycle) engines, however. The present invention could also be used with a two-stroke (or two-cycle) engine in which the end of the combustion stroke and the beginning of the compression stroke happen simultaneously and the intake and exhaust functions are performed at the same time.
The air-fuel mixture is introduced into the combustion chamber in one of two ways—by a carburetor or a fuel injection system. With a carburetor, the air-fuel mixture is drawn or sucked into the combustion chamber through the intake valve as the piston moves downward, thereby decreasing the pressure in the combustion chamber. At start-up of the engine, the ratio of air to fuel in the air-fuel mixture is controlled by a choke plate that is situated just inside of the carburetor throat. Gasoline is drawn into the air flow inside of the carburetor from a fuel bowl inside the carburetor between the carburetor throat and the throttle valve. The throttle valve controls the flow of the air-fuel mixture into an intake manifold, which in turn holds the air-fuel mixture until it is drawn into the combustion chambers by the pressure differential created by the downwardly moving pistons.
With a fuel injection system, gasoline is sprayed directly into the combustion chamber (direct fuel injection), into the intake manifold port in the intake manifold outside of the combustion chamber (ported fuel injection), or into a carburetor body (throttle body fuel injection). The present invention, which is a modified piston design, can be used with engines that have carburetors or fuel injection systems.
In a conventional reciprocating engine (i.e., one that does not utilize the present invention), not all of the air-fuel mixture that is introduced into the combustion engine is burned or combusted. This lack of combustion results in environmentally harmful emissions. The greater the percentage of air-fuel mixture that is combusted, the lower the emissions—and vice versa.
Various methods of reducing emissions have been invented over time, and a thorough review of all such inventions is beyond the scope of this application; however, four notable attempts at reducing emissions include positive crankshaft ventilation, exhaust gas recirculation, the air injection method, and the catalytic converter. With positive crankshaft ventilation and exhaust gas recirculation, polluting exhaust fumes are added to the air-fuel mixture and burned a second time. The air injection method involves pumping fresh air into the exhaust manifold to increase oxidation and destroy harmful hydrocarbons. Catalytic converters contain compounds that react with hydrocarbons in exhaust gases to convert them to less harmful compounds. The present invention is more efficient than any of these emissions reduction methods and may eliminate the need for catalytic converters altogether.
One of the problems with conventional reciprocating engines is that there is a stagnant layer of air-fuel mixture on the face (or top surface) of the piston. This layer is often referred to as the “boundary layer,” and it adversely affects the distribution of fuel, flame front propagation, and exhaust gas flow out of the combustion chamber. It also adversely affects other aspects of the dynamic flow of air into, through and out of the combustion chamber. This is because the boundary layer is relatively stagnant and has a relatively higher viscosity than that of the air-fuel mixture adjacent to it in the combustion chamber. Some of the adverse effects of this boundary layer are described more fully below.
First, the boundary layer (which is a layer of air-fuel mixture) allows precipitation of fuel from the air-fuel mixture. The precipitated fuel gravitates onto the top of the piston, particularly around the edges (periphery) of the piston. This pooling of fuel prevents complete fuel combustion from occurring.
Second, the flame front is hindered by the difference in viscosity of the boundary layer relative to the rest of the gasses in the combustion chamber. The hydrocarbons in the fuel tend to create a carbon build-up that adheres to the top of the piston, further hindering proper combustion. If not sufficiently cooled, the hydrocarbon residue will pre-ignite the next air-fuel charge that enters the combustion chamber.
Third, the boundary layer continues to combust during the exhaust stroke of the engine, thereby allowing unburned or incompletely burned fuel to be purged into the exhaust stream. This can lead to combustion occurring in the exhaust system, which is undesirable.
Fourth, the boundary layer interferes with evacuation of the exhaust gasses because of its relatively higher viscosity and the fact that it resides on top of the piston. It also hinders the incoming air-fuel mixture that is drawn or blown into the combustion chamber during the intake stroke.
The present invention solves all of the problems created by the boundary layer on the face of the piston by directing (or shooting) the air-fuel mixture across the surface of the piston and toward the center of the piston, where the spark plug is located. This rapid redirection of the air-fuel mixture wipes the boundary layer off the surface of the piston (i.e., disrupts it) and/or prevents it from forming. Although other inventions have been designed to create general turbulence in the combustion chamber, none of these inventions is specifically directed toward shooting or directing the air-fuel mixture toward the center of the piston through the use of radially configured grooves whose depth and width are specifically tailored to create this shooting action.
Examples of invention designed to create turbulence within the combustion chamber include U.S. Pat. No. 4,063,537 (Lampredi, 1977) (describing a secondary chamber in a combustion chamber for a diesel engine, wherein a central channel induces turbulence in the combustion gasses, and grooves in the piston crown trap gasses escaping from the central channel); U.S. Pat. No. 5,065,715 (Evans, 1991) (providing a piston with a central bowl and a plurality of squish jet channels circumferentially spaced about the bowl, the purpose of the jet channels being to direct air-fuel mixture into the bowl and to create turbulence within the bowl); U.S. Pat. No. 6,047,592 (Wirth et al. 2000) (disclosing a modified piston with two longitudinal guiding ribs and a cross-guiding rib (to form an H-shaped configuration), one of the purposes of which is to form a tumble flow during the suction (intake) phase and transform the tumble flow into increased turbulence during the late compression phase); U.S. Pat. No. 6,170,454 (McFarland et al., 2001) (describing a piston with a raised portion increasing in height from the center of the piston toward the perimeter and with a plurality of dimples on the raised portion for creating eddies (or turbulence) within the air-fuel mixture); and U.S. Pat. No. 7,810,479 (Naquin, 2010) (in a preferred embodiment, providing a piston with three parallel grooves extending across the width of the piston face, the inventor claiming that combustion efficiency of an engine is related to the level of turbulence in the combustion chamber and that fluid flow is converted from laminar to turbulent when it exits the grooves in the piston face).
U.S. Pat. No. 4,471,734 (Showalter, 1984) discloses a modified piston top comprising long and short slots arranged in a radial configuration. The slots are designed to break up the roll-up vortex that forms on the top of the piston starting at the cylinder wall. (The vortices of the present invention start at the center of the piston.) This roll-up vortex is described as a direct consequence of the relative motion between the piston and the boundary layer near the surface of the cylinder (presumably the cylinder wall). These vortices are the exact opposite of the vortices created by the present invention in that they move radially inward (the vortices of the present invention move radially outward). According to the inventor, the hydrocarbons in these vortices do not burn; therefore, the purpose of the invention is to break up these vortices and create turbulence within the combustion chamber.
U.S. Pat. Nos. 7,581,526 (Lehmann, 2009) and 7,721,704 (Lehmann, 2010) involve a piston design with a plurality of vanes extending “axially,” which the inventor has defined as in the direction of the thrust line of the piston (i.e. the vanes extend upwardly from the piston face). Each vane comprises two walls. The walls may be planar or curved, and they may intersect one another or be joined by a connecting surface (as in a plateau on the top of a mountain). In one embodiment, the vanes are arranged in a radial configuration. In all embodiments, the distance between the walls of the vane is greater proximate the piston (nearest the piston face) than at the distal end of the vane (farthest from the piston face). The vanes are part of a device that is attached to the top surface of the piston crown by welding, bolts or other connecting means; in an alternate embodiment, the piston and device are unitary in construction. According to the inventor, the vanes may differ in height on a single device. The vanes create vortices in the air-fuel mixture in the combustion chamber, and these vortices are more perpendicular than parallel to the direction of movement of the piston. | {
"pile_set_name": "USPTO Backgrounds"
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A mobile network may comprise a plurality of mobile stations ('cell phones) used by the users to communicate. For example, a first user may communicate with a second user using voice communication (speech) and text messaging (short message service, SMS) features supported by the cell phones. However, the users may lose their cell phones or forget the location in which the cell phone is placed. For example, the first user may call his/her cell phone and based on the ringing sound generated by the cell phone, the first user may determine the physical location of the cell phone. However, while the cell phone is lost, if the cell phone is ‘turned-off’ mode or ‘silent mode’, it may be difficult for the first user to determine the physical location of the cell phone. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to an image processing apparatus which has a function of transmitting input image data to an external device, and a method for controlling the image processing apparatus.
2. Description of the Related Art
Various systems for an image processing apparatus to transmit input image data to an external device such as a personal computer (PC) and store the image data have been used. For example, some systems have been used as a scanning system for transmitting image data generated by reading a document image using a scanner to an external device such as a PC.
One is a system for a user to use a scanner driver installed in a PC which is a transmission destination of image data, to operate the scanner driver on the PC, transmit a scan instruction to a scanner to perform scanning, and acquire the image data. This system is used for the PC to acquire the image data from the scanner which is referred to as a “Pull scanning system (hereinafter referred to as Pull scanning)”.
The second is a system for a user to directly operate an operation panel of a scanner, input a scan instruction after designating a transmission destination of image data to perform scanning, and transmit the image data to a PC at the transmission destination. This system is used for the scanner to transmit the image data to the PC which is referred to as a “Push scanning system (hereinafter merely referred to as Push scanning)”. In the Push scanning system, protocols such as File Transfer Protocol (FTP), Server Message Block (SMB), and Simple Mail Transfer Protocol (SMTP) are generally used to transmit the image data to the PC via a network.
The third is a system for a user to directly operate an operation panel of a scanner, and transmit an instruction to execute Pull scanning to a PC selected on the operation panel. The PC that has received the instruction to execute Pull scanning starts the Pull scanning using a scanner driver installed in the PC. In this system, the user designates scan settings such as a reading condition previously set by the scanner driver on the operation panel of the scanner, and the scanner driver executes the Pull scanning according to the scan settings. In this system, the user need not operate the PC, as in Push scanning, and issues a scan instruction on the operation panel of the scanner. However, the PC then acquires the image data from the scanner, as in the Pull scanning. Therefore, the system is referred to as a “pseudo Push scanning system (hereinafter merely referred to as pseudo Push scanning)”.
As described above, in the Pull scanning, the scan instruction is received from the PC (scanner driver) which is the transmission destination of the image data. Therefore, the transmission destination of the image data is uniquely specified. On the other hand, in the Push scanning and the Pseudo Push scanning, a method for displaying information representing a list of transmission destinations previously registered in the scanner on the operation panel of the scanner and making the user select the transmission destination from the list has been considered (Japanese Patent Application Laid-Open No. 2003-198819).
When the transmission destination of the image data is selected on the operation panel in the image processing apparatus, as in the Push scanning and the pseudo Push scanning, as described above, the following issue occurs. When PC names representing the transmission destinations overlap in a plurality of PCs and a user who operates the operation panel in the image processing apparatus selects one of the PCs having the overlapping name without noticing it, image data is transmitted to the PC different from the PC intended by the user. Thus, erroneous transmission of image data may occur.
On this issue, when the PC name representing the transmission destination is registered in the image processing apparatus, the PC name may be inhibited from being registered if it overlaps the other PC name. However, when a model name of the PC, for example, is automatically registered in the image processing apparatus by information notified from the scanner driver, inhibition of the registration and automatic change of the registered name may rather degrade operability. Although the registered names are not actually identical, characters, in a portion displayed on the operation panel in the image processing apparatus, of the names may be identical. In such a case, a method for inhibiting the overlapping name from being registered is not necessarily an effective measure. | {
"pile_set_name": "USPTO Backgrounds"
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On a computer, a user must typically perform multiple tasks while maintaining and utilizing applications and controlling the applications being used. The user must typically accomplish all of these numerous tasks in a limited amount of space on the display. Therefore, the user is often faced with the dilemma of not being able to perform a computer task while simultaneously controlling an application. Such shortcomings might be due, for example, to problems with limited display workspace.
Previously, systems have attempted to alleviate the problem of managing the workspace on the display by providing a mechanism by which the user may minimize windows to a taskbar. In this method, a user may minimize a window to the taskbar such that the window is no longer visible on the display and therefore does not take up significant space. In this way, the user may continue to perform the main computer task while other applications are available but not visible. However, when the application window is minimized, the user may no longer control that application without first re-opening the corresponding window. When an application window is minimized to the taskbar, the resulting taskbar button might contain the name of the application. Even though the user may determine what application is associated with a taskbar button, the user is not able to perform tasks with the application that has been minimized to the taskbar. In order to control the application, the user must re-open the application window. After performing an operation on the application in the open window, the user must then close the window again to free up workspace on the display. In so doing, the user must divert his/her attention to opening (and closing) the application window and performing steps necessary to control the application. Moreover, when the application window is re-opened, space is occupied by the re-opened window further forcing the user to suspend activities in order to manage the additional opened window.
User frustration results from this tedious and time-consuming method of minimizing application windows and re-opening (and closing/minimizing) the windows when control is desired. The user must interrupt his/her computer work in order to open and close windows. This leads to a precipitous decline in efficiency as the user wastes time managing open windows on the display.
Thus, there exists a need in the art for a system and method for providing convenient application control to a user through custom user interfaces without waste of display workspace. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to an apparatus for detecting the breaking of a glass plate, and more particularly to such apparatus for detecting the vibration of a glass plate which occurs when the glass plate gets broken or damaged, so as to detect the breaking or damage of the glass plate.
It is known that when a glass plate having a piezoelectric element mounted thereon gets broken or damaged a mechanical vibration is produced. The electrical signal produced by the piezoelectric element due to mechanical vibration-to-electrical signal conversion has signal components not only in a low frequency range such as 20 to 30 kHz but also in a high frequency range higher than 100 kHz. Japanese laid-open patent publication (non-examined) NO. 48-66485/1973 based on British patent application No. 57598/71 discloses an apparatus which detects the breaking of a glass plate by detecting the converted electric signal with a frequency above 100 kHz only. According to the teaching of the above cited Japanese laid-open patent publication No. 48-66485/1973, the detection of signal components in a low frequency range lower than 100 kHz is avoided, so as to prevent erroneous detection of the breaking of the glass plate.
However, it has been found that signal components higher than 100 kHz appear at the output of the piezoelectric element not only when the glass plate gets broken but also when sand, a small stone, a small metal body or the like collides with the glass plate. This leads to an erroneous detection of the breaking of the glass plate | {
"pile_set_name": "USPTO Backgrounds"
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This application relates to devices, techniques and materials related to biofuels.
In general, fossil fuels in modern engines provide incomplete combustion and create adverse heat transfers, particularly in automotive engine applications. In large part, this is because conventional operation of engines provides for homogeneous-charge combustion and allows quenching of fuels undergoing combustion with consequent heat losses to the piston, cylinder walls, and head components along with pollutive emissions. After quenching of combustion, partially burned fuel constituents pass out of the combustion chamber to the exhaust system to cause further efficiency losses and pollution of the atmosphere. In both homogeneous-charge and diesel engine operations, liquid fuel droplets must be evaporated and depolymerized or “cracked” to promote combustion. These processes require heat from the air or from the combustion of other fuel constituents and considerable time for these events to be completed in order to complete the combustion process. About ⅓ of the heat released by combustion is lost through the cooling system of the engine and is dissipated to the environment through the radiator. Engines are designed to open the exhaust valve when the hot combustion gases still have considerable pressure and thus substantial amounts of heat and pressure potential energy is lost through the exhaust system. About ⅓ of the heat released by combustion is lost through the exhaust system of the engine and is dissipated to the environment.
In order to provide for marginal relief from atmospheric pollution, fuel purveyors have promoted more complete combustion of fossil fuels by additions of supplements such as methyl tertiary butyl ether or “MTBE” a compound with the molecular formula C5H12O. However because of groundwater water contamination by MTBE a more recent practice has been to add ethanol a compound with the formula C2H5OH. The concentration of such oxygenated additives has been about 5% to 10% of the total fuel mixture. In practice it has been shown that such additions of oxygen at the carbon to oxygen ratio of 5:1 or 2:1 for a relatively small fraction of all the fuel molecules present in the combustion process helps promote more complete combustion by providing oxygen for oxidation of other fuel constituents. Nevertheless, considerable additional expense is incurred for catalytic reactors for attempts to marginally reduce air pollution from engines using hydrocarbon fuels with additions of ethanol. Such air pollution remains objectionable particularly in congested cities and can cause or exacerbate lung diseases, heart and circulatory problems, corrosion of construction materials and contributes to greenhouse gas accumulation problems. | {
"pile_set_name": "USPTO Backgrounds"
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This application relates generally to combustors and, more particularly, to gas turbine combustors.
Air pollution concerns worldwide have led to stricter emissions standards both domestically and internationally. Aircraft are governed by both Environmental Protection Agency (EPA) and International Civil Aviation Organization (ICAO) standards. These standards regulate the emission of oxides of nitrogen (NOx), unburned hydrocarbons (HC), and carbon monoxide (CO) from aircraft in the vicinity of airports, where they contribute to urban photo chemical smog problems. In general, engine emissions fall into two classes: those formed because of high flame temperatures (NOx), and those formed because of low flame temperatures which do not allow the fuel-air reaction to proceed to completion (HC and CO).
At least some known gas turbine combustors include between 10 and 30 mixers, which mix high velocity air with a fine fuel spray. These mixers usually consist of a single fuel injector located at a center of a swirler for swirling the incoming air to enhance flame stabilization and mixing. Both the fuel injector and mixer are located on a combustor dome.
In general, the fuel to air ratio in the mixer is rich. Since the overall combustor fuel-air ratio of gas turbine combustors is lean, additional air is added through discrete dilution holes prior to exiting the combustor. Poor mixing and hot spots can occur both at the dome, where the injected fuel must vaporize and mix prior to burning, and in the vicinity of the dilution holes, where air is added to the rich dome mixture.
One state-of-the-art lean dome combustor is referred to as a dual annular combustor (DAC) because it includes two radially stacked mixers on each fuel nozzle which appear as two annular rings when viewed from the front of a combustor. The additional row of mixers allows tuning for operation at different conditions. At idle, the outer mixer is fueled, which is designed to operate efficiently at idle conditions. At high power operation, both mixers are fueled with the majority of fuel and air supplied to the inner annulus, which is designed to operate most efficiently and with few emissions at high power operation. While the mixers have been tuned for optimal operation with each dome, the boundary between the domes quenches the CO reaction over a large region, which makes the CO of these designs higher than similar rich dome single annular combustors (SACs). Such a combustor is a compromise between low power emissions and high power NOx.
Other known combustors operate as a lean dome combustor. Instead of separating the pilot and main stages in separate domes and creating a significant CO quench zone at the interface, the mixer incorporates concentric, but distinct pilot and main air streams within the device. However, the simultaneous control of low power CO/HC and smoke emission is difficult with such designs because increasing the fuel/air mixing often results in high CO/HC emissions. The swirling main air naturally tends to entrain the pilot flame and quench it. To prevent the fuel spray from getting entrained into the main air, the pilot establishes a narrow angle spray. This may result in a long jet flames characteristic of a low swirl number flow. Such pilot flames produce high smoke, carbon monoxide, and hydrocarbon emissions and have poor stability.
In an exemplary embodiment, a combustor for a gas turbine engine operates with high combustion efficiency and low carbon monoxide, nitrous oxide, and smoke emissions during low, intermediate, and high engine power operations. The combustor includes a mixer assembly including a pilot mixer, a main mixer, and a mid-power and cruise mixer. The pilot mixer includes a pilot fuel injector, at least one swirler, and an air splitter. The main mixer extends circumferentially around the pilot mixer. The mid-power mixer extends circumferentially between the main and pilot mixers, and includes a plurality of fuel injection ports and an axial air swirler that is upstream from the fuel injection ports.
During idle engine power operation, the pilot mixer is aerodynamically isolated from the main mixer, and only air is supplied to the main mixer. During increased power operations, fuel is also injected radially inward and supplied to the mid-power mixer, and the mid-power mixer axial swirler facilitates radial and circumferential fuel-air mixing. As the gas turbine engine is further accelerated to high power operating conditions, fuel is then also supplied to the main mixer. The main mixer conical swirler facilitate radial and circumferential fuel-air mixing to provide a substantially uniform fuel and air distribution for combustion. As a result, the fuel-air mixture is uniformly distributed within the combustor to facilitate complete combustion within the combustor, thus reducing high power operation nitrous oxide emissions. | {
"pile_set_name": "USPTO Backgrounds"
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In an aircraft gas turbine engine, a large number of sensors are provided in various parts thereof and the output values of these sensors are used for optimally controlling the operation of the engine. A fault in any one of such sensors may cause abnormal values in the control parameters, and prevents satisfactory operation of the engine. Therefore, it is highly important to take appropriate measures in case of a sensor failure.
A fault of a sensor can be detected in come cases by comparing the output value of the sensor with a certain limit value or the change rate of the output value of the sensor with a prescribed threshold value. See Japanese patent laid-open publication No. 6-264767, for instance.
However, this known technology is only suitable for detecting misfire when starting the engine, and is not suitable for promptly detecting a fault in a sensor during the normal steady-state and transient operation of the engine. Also, to permit detection of an abnormal output of each one of a large number of sensors, a same number of reference maps as the number of the sensors are required for evaluating every one of the sensors. This undesirably increases the complexity of the control program.
In the case of a gas turbine engine including a high pressure shaft and a low pressure shaft that are disposed in a coaxial relationship, it is also known to define a prescribed relationship between the rotational speeds of the high pressure shaft and low pressure shaft, and judge that at least one of the sensors is faulty when the output values of the rotational speed sensors for the high pressure shaft and low pressure shaft deviate from the prescribed relationship beyond a certain threshold. See Japanese patent laid open publication No. 2000-249629.
Again, this known technology is capable of achieving any reliability only in a limited operating range, and is unable to detect a fault in the sensors in the high speed and/or transient operating mode of the engine. | {
"pile_set_name": "USPTO Backgrounds"
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Implantable medical devices (“IMD”) are used today for various applications to deliver electrical pulses from a pulse generator within the IMD, through an electrical lead connected to the IMD, to a targeted location within a patient's body. For instance, pacemakers are used to deliver electrical pulses generated within a pulse generator through an electrical lead to a patient's heart to maintain proper rhythm. In order to deliver those pulses, the electrical pulse from the generator is delivered through a lead connector assembly to a plurality of electrical contacts at one end of the lead, which lead then carries the electrical pulses to electrical contacts at the opposite end of the lead which are positioned adjacent the portion of the patient's heart that is to be stimulated.
Similarly, IMD's may be used in neurological applications, such as for deep-brain stimulation and spinal cord simulation, in which leads deliver electrical pulses generated in the IMD to targeted portions of a patient's brain or spinal cord.
In still other applications, leads may be used to sense particular conditions within a patient's body, and relay that sensed condition back to a processing unit within the IMD.
Many IMD's include a housing that houses the circuitry of the IMD, a connector block that connects the lead or leads to the IMD, and one or more leads inserted into the connector block to transfer electrical pulses generated within the IMD to the targeted portion of the patient's body. Many such connector blocks include female receptacles into which the male end of a multicontact lead may be inserted; however, the female receptacles are provided on only one end of the connector block. This configuration of the female receptacle of the header or connector may have a limiting effect on the number and types of leads that may be operated with a single implantable medical device. For instance, a connector block might have two receptacles, each providing 12 electrical contacts configured to receive a 12-contact lead. This configuration can be useful where the patient's condition requires the delivery of electrical stimulation using 12-contact leads, such as a 12-contact percutaneous electrode. If, however, the patient's condition changes such that an alternate configuration is desired (such as using 3 8-contact leads to more disparately apply the electrical pulses across a broader area), an alternative connector block must be provided that provides 3 8-contact receptacles. Requiring such a change of the IMD to receive an alternative lead configuration can be quite expensive and clearly uncomfortable and undesirable for the patient. Likewise, as doctors may have varied preferences for how and in what configuration electrical pulses should be delivered to a targeted portion of a patient's body (based on a particular patient's diagnosed condition), providing separate connector blocks for every possible configuration the doctor might come across can likewise become quite costly, as it significantly complicates the inventory that the doctor must maintain.
Therefore, it would be desirable to provide an improved connector block for an implantable medical device that could be variably configured to adapt to varied clinical conditions so as to allow the delivery of electrical pulses from an IMD in such varied clinical conditions using only a single, standard connector block.
Moreover, in some operative environments, operative space may be limited for inserting a lead longitudinally into the connector block on the IMD. In such environments, it would be desirable to provide an improved connector block that could allow insertion of leads into the connector block without requiring their longitudinal insertion, and that was otherwise configurable to minimize the amount of space that must be available in the operative environment to engage the leads with the connector block assembly. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field
The present disclosure relates generally to solar power systems and, in particular, to solar power collectors. Still more particularly, the present disclosure relates to a method and apparatus for pointing solar power collectors.
2. Background
Solar power may involve converting solar radiation into electricity through solar cells. The solar cells are solid state devices that convert sunlight into electricity using a photovoltaic effect. Assemblies of these solar cells form solar modules, which are also referred to as solar collectors or just collectors.
Solar power plants use large numbers of these collectors. A collector may have different sizes. For example, a collector may be from about two square meters in size to over 10 square meters in size.
With the use of solar cells that employ photovoltaics to generate electricity, the orientation of these collectors may affect the amount of electricity generated. It is desirable to have a vector normal to the surface of a collector directed or pointed towards the sun. As the orientation of the collector deviates from this desired direction, the amount of electricity generated by the collector may decrease.
Depending on the particular system, the tolerance or range in pointing the collectors may be important in increasing the amount of electricity that can be generated by the collectors.
In some solar power systems, concentrating photovoltaics are used. These types of systems may include lenses, mirrors, or a combination of the two to focus sunlight on the photovoltaic cells in the collectors. These concentrators may increase the concentration ratio. For example, the concentration ratio may be about 400 to about 1,000 times the amount of light received from unconcentrated sunlight. With collectors that employ concentrators, the accuracy in pointing the collector towards the sun may be even more important, as compared to collectors that do not use concentrators.
Therefore, it would be advantageous to have a method and apparatus that takes into account at least some of the issues discussed above, as well as possibly other issues. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a data processing apparatus, a data processing method, and a data processing system that allow a potable music reproducing device to search for a song.
2. Description of the Related Art
In recent years, portable reproducing devices that receive song data from Compact Discs (CDs) as music information sources and that allow the users to enjoy listening to music have been widely used. With the improvement of audio compression technology, a very large number of songs for example several hundred songs or several thousand songs of song data can be stored to a medium such as a Compact Disc-Recordable (CD-R) disc, a semiconductor memory, a small hard disc, or the like. The audio compression technology is for example Moving Picture Experts Group audio layer 3 (MP3), Adaptive Transform Acoustic Coding (ATRAC3, registered trademark), Adaptive Transform Acoustic Coding 3 plus (ATRAC3 plus, registered trademark), Advanced Audio Coding (AAC), Windows Media Audio (WMA, registered trademark).
Song data can be obtained from commercial CDs. In addition, using Electric Music Distribution (EMD), the user can obtain a wide variety of song data. The user selects and reproduces a desired song from many songs of song data recorded on a medium such as a CD-R disc on a portable reproducing device for example a portable CD player. When the user selects a desired song, he or she normally searches for the desired song corresponding to a song name and an artist name that are displayed on a liquid crystal display section of the main body of the player or a liquid crystal display section of a remote controller. In other words, while the user is watching data on the liquid crystal display, he or she searches for his or her desired song with indicators of a song name, an artist name, and so forth that he or she is watching.
The following patent document 1 describes a multi-CD player that pre-stores a part, for example the beginning, of each song of song data of each CD in a high speed memory and that has a scanning mode that allows the player to reproduce a part of the pre-stored song data at high speed. With the scanning mode, the user can quickly select a CD to reproduce song data. [Patent Document 1] Japanese Patent Laid-Open Publication No. 2000-123463 | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a process recovery of catalyst components from a reaction mixture and particularly to reaction mixture from oxidative direct carbonylation.
A process for the removal and recovery of quaternary salt (A) and base (D) from a reaction mixture is disclosed. The reaction mixture resulting from oxidative direct carbonylation contains in addition to (A) and (D), at least one hydroxyaromatic compound (B) and at least one reaction product (C) and optionally a solvent, and the process entails
a) adding acid to the reaction mixture to cause conversion of (D) into a hydroxyaromatic compound (B2) b) separating the reaction mixture into b1.) that contains (C) and optionally (B) and/or (B2) and b2.) that contains (A) and optionally (B) and/or (B2), and c) reacting b1.) with a base (E) to re-form (D).
During the oxidative direct carbonylation of aromatic hydroxy compounds in the presence of CO, O2 a noble metal catalyst, preferably palladium, and also an inorganic cocatalyst (e.g. manganese, or cobalt salts), a base, a quaternary salt, various organic cocatalysts (e.g., quinones or hydroquinones) and drying agents are generally used (see e.g. DE-OS 27 38 437, U.S. Pat. No. 4,349,485, U.S. Pat. No. 5,231,210, EP-A 677 336, EP-A 858 991, U.S. Pat. No. 5,760,272). The process may be performed in a solvent.
After performing the reaction, product mixtures are obtained from these reactions which contain, inter alia, one or more quaternary salts A, a hydroxyaromatic compound B, reaction products C such as e.g. water and diaryl carbonates, a base D (incl. any being produced by deprotonation of a hydroxyaromatic compound with another base or the directly used salt of a hydroxyaromatic compound) and possibly solvent, additional catalyst components, auxiliary substances and impurities. Thus, there is the object of separating one or more products C from quaternary salts and bases (A and D), without decomposing sensitive products C and also recycling A, B and D to the reaction as quantitatively as possible without any of the impurities present in the reaction mixture.
The working-up of such streams in the absence of D, by an extraction and precipitation process, is disclosed in EP A1 913 197. However, this working-up process does not lead directly to re-useable products without impurities.
An extraction process for recovering bromide salts from reaction mixtures similar to those in the present application is disclosed in U.S. Pat. No. B 6,310,232. Here again, however, the process does not lead directly to re-useable products A, B and D. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a polyethylene composite film suitable for packaging, which is superior in moisture-proofness, flexocracking resistance, tearability and heat sealability.
2. Description of the Prior Art
Up to the present time, as conventional packaging films have been known three layer structures each consisting of a surface layer of a heat resisting material such as paper, polyethylene terephthalate film (PETP), biaxially oriented polypropylene film (OPP), cellophane, oriented polyamide film (OPA) or the like, an intermediate layer of a gas barrier material such as saponified ethylene-vinyl acetate copolymer film (saponified EVA), aluminum foil (Al) or the like, and a sealant layer. However, these surface layers meet with the problems that the flexocracking resistance, moistureproofness and tearability are not sufficient to make up the performance of the intermediate layer and the surface layers need provision of sealant layers in uses, for example, gusset bags in which surface layer materials must have sealability each other, thus resulting in increase of the production cost, since the surface layers have no sealability.
On the other hand, a polyethylene film excellent in moisture proofness, clarity and tearability has been proposed which is crosslinked and oriented in such a manner that the degree of crosslinking is specified in the thickness direction (Japanese Laid-Open Publication Nos. 174321/1984 and 174322/1984). However, this crosslinked and oriented polyethylene film has excellent properties as a packaging film, but the heat sealability of this film itself or a laminated film using this film as a sealant is not always sufficient, in particular, in the case of making a heat-sealed bag by contacting the film with a heat sealing bar at a high temperature at a high speed.
Furthermore, a polyethylene composite film has also been proposed which consists of a crosslinked and oriented polyethylene film excellent in moistureproofness and clarity, having a specified degree of crosslinking in the thickness direction of the film, and a sealant layer of a low density polyethylene (Japanese Patent Laid-Open Publication No. 171149/1985). However, this polyethylene composite film has also a disadvantage in the heat sealability of the films one another.
As a film with a good tearability, cellophane or longitudinally or laterally monoaxially oriented polyethylene film (MOPE) has been known. However, the cellophane surely has a good self tearability property, but the straight line tearability is not good, and the monoaxially oriented polyethylene film has the disadvantage that the straight line tearability is good, but a clear tearability is hardly obtained because of tendency of occurrence of fibrils during cutting.
A standing pouch using a packaging film, of the conventional packagings, needs the straight line tearability. To this end, for example, there have been proposed laminated films with lamination structures of polyester film (PET film)/aluminum foil (Al foil)/MOPE film/non-oriented polypropylene film (CPP film) and PET film biaxially oriented nylon film (O-Ny film)/MOPE film/low density polyethylene film (LDPE film). However, these laminated films have also disadvantage of occurrence of fibrils and accordingly, it has eagerly been desired to develop a packaging film with more excellent linear and clear tearability. | {
"pile_set_name": "USPTO Backgrounds"
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Electromagnetic components, such as inductors and filters, are used in a variety of applications. In many industrial applications, inductors and filters are integral components in a wide array of machines. Important factors in the design of electromagnetic components, such as inductors include: cost, size, heat dissipation, noise level, efficiency, and inductance capacity.
Elements and steps in the figures are illustrated for simplicity and clarity and have not necessarily been rendered according to any particular sequence. For example, steps that are performed concurrently or in different order are illustrated in the figures to help to improve understanding of embodiments of the present invention. | {
"pile_set_name": "USPTO Backgrounds"
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A playback mode for going back a prescribed time interval to play back recorded data of, for example, a television program while recording the program on a recording medium is widely used as a time-shifted playback mode. Time-shifted playback is a mode of playback that starts playback of an already recorded program from the start of the program and uses double-speed reproduction with sound to chase the real-time broadcast, and is therefore also referred to as “chase playback.” In time-shifted playback, the user can, while recording a received broadcast signal onto a recording medium, play back and view at the user's desired speed (for example, fast-forward or slow-motion playback) or, as necessary, repeat playback and viewing of specific points. As a result, this mode provides a viewing environment that affords the user a great degree of freedom.
As a broadcast signal-providing device of the related art, a method has been considered for, upon the detection of an incoming call in a mobile telephone when a television function is in operation, implementing a process for starting a recording operation and holding the recording starting point and then starting a playback operation from the recording starting point upon termination of the conversation on the mobile telephone (for example, JP-A-2005-223778). In this configuration, when television viewing is interrupted by an incoming telephone call or the arrival of a guest, the user can still return to the point of interruption and view the missed program.
In addition, a method has been considered in which, in a portable telephone having a television reception function, a control unit executes a process for storing the received broadcast signal in a storage means upon input of a signal of the start of a conversation and executes a process for playing back the broadcast signal that was stored in the storage means upon input of a signal indicating the end of the conversation (for example, JP-A-2005-117149). In this type of configuration, even when there is an incoming call from the telephone of an acquaintance, when the user is viewing a television program on a portable telephone, the user can resume viewing of the stored television program once the conversation (communication) with the acquaintance ends.
As described above, the broadcast signal-providing device of the related art is of a configuration provided with a playback means and recording means for starting recording of a television program by the recoding means upon the occurrence of an event that interrupts television viewing such as the start of a conversation and such as playing back the recorded data by the playback means from the point of interruption when the event ends. By means of this configuration, viewing can be easily resumed by returning to the point of interruption. However, a broadcast signal-providing means of this type has several problems as described below.
First, in the device of the related art, the broadcast signal is merely recorded on the recording medium in the order recorded and the information (content) then played back with a time shift in the order received, and even when traffic congestion information, weather information, or event information for which there is a need for immediacy (information that should be viewed immediately) is included in the broadcast signal, this information is similarly time-shifted. The problem therefore arises that the viewer is unable to immediately view information demanding immediate attention. In particular, when the viewer replays content or temporarily halts playback and thereby increases the time shift of the time difference between the time of recording and the time of playback, the viewing of information such as weather information that is immediately required is delayed and the possibility arises that the viewer will mistakenly apply the information.
The second problem is that when information that calls for immediacy is viewed with a time shift, changes in conditions that have occurred during the interval of time shift are not reflected. The problem therefore arises that the viewer is provided with information that does not correspond to changes in conditions. For example, when event information having the content that “tickets are still available” is broadcast on television, the viewer, upon viewing this event information with a time shift may be caused to mistakenly believe that tickets are available even though tickets have already been sold out at the time the viewer views the information.
The third problem is that information having a high degree of immediacy (for example, information regarding a typhoon, earthquake, or other event) is often inserted as a flash report into the content of regular broadcasts (during a regular television program), and the insertion of this information into a regular broadcast interferes with the ambience of the content of the regular broadcast. Even though information having a high degree of immediacy is information that must be provided to the viewer immediately and must therefore be inserted into a regular broadcast, the interference with the ambiance of a program resulting from viewing information that has already lost newness when viewing content that has undergone a time shift is an inconvenience for the viewer. | {
"pile_set_name": "USPTO Backgrounds"
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Bidirectional communication systems are ubiquitous in modern society, with one example being the telephone system, and another being bidirectional or interactive cable television. It is ordinarily advantageous to use a single transmission path for the bidirectional transmission, to reduce the number of conductors or optical fibers extending between the stations which are communicating. When a bidirectional signal path is used, the equipment at each end must ultimately separate the signals into incoming and outgoing portions, so that they may be applied to the appropriate one of a display device or earphone, and so that signals produced by a camera or microphone at the same location do not interfere with the signal received from a remote location. The separation of signals in response to their direction of transmission is accomplished by a device known as a hybrid. When operating properly in a telephone system, the hybrid isolates the signals flowing in different directions from each other, and prevents "echoes" or ringing which arise from a tendency toward signal oscillation which results from circulation of transmit signals in a receive unit which leak into the receive unit and back into the transmit path. Hybrids exhibit optimum performance, defined as transmit-to-receive isolation, when the minimum amount of transmit signal appears at the receive signal port. This maximum isolation is achieved when the bidirectional signal transmission path presents an impedance to the bidirectional signal port of the hybrid which matches the impedance for which the hybrid is designed. Desirable isolation may range from about 30 to 50 dB, depending upon the application. Isolations as low as 10 dB may result from transmission-path impedances which deviate by a factor of two or three from the design impedance. Thus, impedances which are two or three times the hybrid design impedance, or which are one-half or one-third the design impedance, may adversely affect the isolation.
Unfortunately, the impedance presented by the bidirectional signal path to the hybrid depends upon such factors as the number of terminal units, as for example telephone units, connected thereto, and the characteristics of the individual terminal units. The load impedance presented to a hybrid may change dynamically during operation, as might occur if an extension telephone is picked up during a conversation already in progress. The problems resulting from such impedance changes have in the past often been ignored, or corrected by digital echo cancellers. Digital echo cancellers rely on voice activation, and as a result may have short periods of echo which are detectable by the user. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field
The present application relates generally to the operation of data networks, and more particularly, to methods and apparatus for providing a control channel in a data network.
2. Background
Typical wireless delivery systems are client-server based systems. Thus, the actions performed by a client may be dependent on one or more server states. For example, the server state may include content states, program guide states, administrative states, or any other type of server state. Thus, the state of a particular distribution system may include information from a number of servers such as a subscription server, distribution server, administrative server, or any other server. At any given time, the state of one or more of these servers may change.
Unfortunately, a device in a wireless distribution system goes in and out of service due to power-down operation modes or limitations in service coverage. Thus, a client operating at a device may have a problem monitoring what is going on in the network. One approach to solve this problem is for the client at the device to completely synchronize its state with all servers in the system before the client performs any action. However, this is inefficient if some server states have not changed or if server states change infrequently. Additionally, if a server's state has not changed, this technique may require the device to utilize power and network bandwidth to obtain state information it may already have.
Therefore, what is needed is a system that operates to provide a way for the state of a distribution system to be efficiently delivered to a wireless device. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a technique for changing various setting items of a device from a terminal device side.
2. Description of the Related Art
In the related art, devices that are connected directly to terminal devices via networks have been popularized. In such a device, a technique is used in which when various setting items of the device are changed from a terminal device side, setting screen data within the device is supplied to the terminal device. In the terminal device to which the setting screen data is supplied, a screen that includes a set value field in which contents of setting items can be inputted, a transmission button for transmitting a content inputted in the set value field to the device, and a cancel button for canceling a content inputted in the set value field, is displayed for prompting a user to perform an operation such as an input.
However, it is unclear what operation the cancellation in the above-described related art specifically indicates. In addition, there is a demand that it is desired to return to a content previously inputted in the set value field when the cancel button is pressed. | {
"pile_set_name": "USPTO Backgrounds"
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The disclosure of Japanese Patent Application No. 2000-213910 filed on Jul. 14, 2000 including the specification, drawings and abstract is incorporated herein by reference in its entirety.
1. Field of the Invention
The invention relates to a technology for cooling a fuel cell in a fuel cell system.
2. Description of the Related Art
Fuel cells that generate electric power by utilizing an electrochemical reaction between hydrogen and oxygen are expected as a next-generation energy source. During operation (power generation) of a fuel cell, a considerable amount of heat is produced by the electrochemical reaction. Therefore, an ordinary fuel cell system has a cooling apparatus for cooling the fuel cell.
Japanese Patent Application Laid-Open No. 8-184877, for example, describes a cooling apparatus of a fuel cell system. In this apparatus, the fuel cell is cooled through the use of a coolant that includes an antifreezing solution containing water and ethylene glycol.
However, since the antifreezing solution containing water and ethylene glycol is capable of conducting electricity, it is difficult for the aforementioned prior art cooling apparatus in some cases to maintain a sufficiently high level of insulation of the fuel cell system.
It is an object of the invention to provide a technology that allows an easy improvement in the insulation of a fuel cell of a fuel cell system.
A fuel cell system is provided with a fuel cell and a cooling apparatus that cools the fuel cell. The cooling apparatus of the fuel cell system includes a first forced circulation cooling system that cools the fuel cell by forcibly circulating a coolant through a circulation passage that extends through the fuel cell. The cooling apparatus uses an electrically insulating solution as a coolant contained in at least a portion of the cooling apparatus.
In this fuel cell system, the fuel cell cooling apparatus uses an electrically insulating coolant, so that the fuel cell can easily be electrically insulated from the outside. Therefore, it is possible to enhance the insulation of the fuel cell system easily.
The cooling apparatus of the fuel cell system is provided with a second forced circulation cooling system that is independent of the first forced circulation cooling system, and an intermediate cooling system that is operable to exchange heat with the first forced circulation cooling system and with the second forced circulation cooling system. The intermediate cooling system contains the electrically insulating solution as a coolant.
Since the coolant used in the intermediate cooling system is an electrically insulating liquid, this construction eliminates the need to consider electrical insulation with regard to the first and second forced circulation cooling systems. Therefore, it is possible to enhance the insulation of the fuel cell system easily.
The intermediate cooling system of the fuel cell system has a container that houses therein the electrically insulating liquid. The electrically insulating solution exchanges heat with the first forced circulation cooling system and with the second forced circulation cooling system while naturally circulating in the container.
This construction has an advantage of simplifying the construction of the intermediate cooling system.
The electrically insulating liquid contained in the intermediate cooling system of the fuel cell system is allowed to boil in the container with a heat derived from the first forced circulation cooling system.
If boiling heat transfer is utilized, the rate of heat transfer to the electrically insulating liquid increases. Therefore the cooling efficiency can be improved.
Each of the first forced circulation cooling system and the second forced circulation cooling system has a heat exchange acceleration portion that accelerates heat exchange with the electrically insulating liquid in the intermediate cooling system.
This construction may improve the cooling efficiency of the intermediate cooling system.
The second forced circulation cooling system has a heat dissipation portion that dissipates heat to an atmosphere.
This construction may improve the cooling efficiency of the second forced circulation cooling system.
The electrically insulating liquid has an antifreezing property.
This construction may expand the temperature range in which the fuel cell system can be operated.
The electrically insulating solution includes a fluorine-based inert liquid or an insulating oil.
A fluorine-based inert liquid or an insulating oil is electrically insulating and antifreezing properties, and therefore are preferable as an electrically insulating coolant.
The invention may be realized in various forms. For example, the invention can be realized in the form of a fuel cell system, a fuel cell cooling system, a cooling method, and the like. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of Invention
The present invention generally relates to an electrical connecting device to a power source, and more particularly relates to a connecting device applicable to a battery terminal for leading current to an appliance and showing the electrical condition.
2. Related Art
The battery of a vehicle provides power to a variety of devices in the vehicle. There is also a need for the user to connect other electrical appliances, such as vehicular refrigerator, television, audio/video system or global positioning system, to the battery power. An electrical connecting device, as disclosed by U.S. Pat. No. 5,171,169, or a similar one as shown in FIG. 1, can be used for this purpose. The connecting device mainly includes a clamp easily fixed on the battery terminal, and an adapter block electrically connected to the clamp for connecting and disconnecting a plurality of cables of appliances. Some other connector structures may further include fuses for each connecting port to prevent from overload and danger.
When using the aforesaid connectors, the user has to use a testing device, such as a voltage meter, to check if the power is well connected, the voltage is stable, or the fuse has burnt. The situation is rather bothersome if the user doesn""t have a testing device, or isn""t familiar with the device that the user has to prepare the device and learn to use it.
It is therefore a major object of the present invention to provide a connecting device applicable to a vehicular battery terminal for leading current to an appliance and showing the electrical condition through a display unit without the need of using additional testing devices.
To achieve the aforesaid object, a connecting device applicable to a vehicular battery terminal includes at least a conductive main body and a display unit. One end of the main body is formed with a clamp for fixing to a battery terminal and leading power to at least an appliance. The other end of the main body is a carrier for the display unit and cables. The display unit includes a display, a circuit board and a plurality of connecting pins. The connecting pins inserted into the carrier electrically connect the display unit to the main body so that the display will show the electrical status, such as voltage of the battery power. The display can be a liquid crystal display to indicate the voltage or current of the battery power. Some further indicators, such as light emitting diodes, can be used to indicate by flash or light if the fuse of each line is normal. A window can also be mounted on the display unit to protect it from being contaminated by dust. The display unit makes the connecting device displayable with electrical conditions directly without the need of using other testing devices.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of Invention
This invention relates to variable diameter rotors and more particularly to such rotors used in plurality and including mechanism to synchronously vary the diameters of the rotors. In addition, mechanism is provided to limit the diameter of the rotors and, further, the rotors are suspended from tiltable pods and the diameters of the rotors are synchronously varied in response to pod tilting.
2. Description of the Prior Art
While the prior art shows single rotors of variable diameter and plural rotors which are interconnected so as to be driven at the same speed, no prior art is known in which a plurality of rotors vary diameter synchronously and include diameter limit controls. | {
"pile_set_name": "USPTO Backgrounds"
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Complementary metal-oxide semiconductor (CMOS) image sensors are gaining in popularity over traditional charged-coupled devices (CCDs) due to certain advantages inherent in the CMOS image sensors. In particular, CMOS image sensors typically require lower voltages, consume less power, enable random access to image data, may be fabricated with compatible CMOS processes, and enable integrated single-chip cameras.
Generally, CMOS image sensors utilize light-sensitive CMOS circuitry to convert light energy into electrical energy. The light-sensitive CMOS circuitry typically comprises a photo-diode formed in a silicon substrate. As the photo-diode is exposed to light, an electrical charge is induced in the photo-diode. The photo-diode is typically coupled to a MOS switching transistor, which is used to sample the charge of the photo-diode. Colors may be determined by placing filters over the light-sensitive CMOS circuitry.
Typically, CMOS image sensors are fabricated utilizing a capacitance within the photo-diode and a floating capacitance created between transistor connections. These capacitances, however, are characterized by small capacitance values, which cause a high susceptibility to noise and reduce the maximum output signal. Attempts have been made to increase the signal generated by a photo-diode, but these typically only increase the electrical charge generated by the photo-diode and do not necessarily increase the output signal.
Furthermore, CMOS image sensors are typically fabricated utilizing MOS transistors having a polysilicon gate and silicon nitride spacers. This type of transistor, however, introduces a silicon surface trap and leakage. As a result, noise on the output signal increases and the dark signal increases.
Therefore, there is a need for an image sensor that reduces noise and a dark signal and increases charge capacity of the image sensor. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a method for forming a silicide and a method for fabricating a semiconductor device and, in particular, to a technique capable of forming at a low temperature a highly thermostable nickel disilicide (NiSi2) layer having an edge the position of which is finely controllable.
2. Description of the Related Art
The gate lengths of today's field-effect transistors are reduced to submicron scale in order to facilitate denser and faster semiconductor integrated circuits. Also, the surface of the source/drain layers of miniaturized field-effect transistors is silicided in order to inhibit the resistance of the source/drain layer from increasing. For example, Nitrogen-doped nickel monoSilicide technique for deep submicron CMOS salicide, IEDM 1995, pp. 453-456 (hereinafter referred to as Non-Patent Document 1) discloses a technique for applying nickel monosilicide (NiSi) that can be formed by annealing at low temperatures on the order of 400° C. to a CMOS. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field Of The Invention
This invention relates to antibody hybride. More particularly, it relates to antibody hybrids in which an organic moiety is covalently bonded to the antibody at a preselected location on the antibody so as to preserve the normal functionality of the antibody.
Antibody molecules exist in one of several classes. To date, five known classes (isotypes) in the higher vertebrates are designated as immunoglobulin (Ig) IgM, IgA, IgG, IgD, or IgE. The common structure for these immunoglobulins is a monomer composed of two heavy chains and two light chains. Heavy and light chains are covalently linked to each other by disulfide bonds and the two heavy chains are linked through disulfide bonds. Two of the immunoglobulin classes, IgM and IgA, exist naturally in a polymeric form. Polymers of the four chain structures are linked via the cysteine residue located in proximity to the carboxyl terminus on the constant region of the heavy chains.
The first step of polymerization of IgM or IgA is dimer formation. In the usual naturally occurring situation the penultimate carboxyl cysteine residue of two monomers are joined via a 20,000 dalton polypeptide joining or `J` chain. After dimerization, pentamer formation of IgM is completed enzymatically by a thiol oxidoreductase. Richard A. Roth and Marion E. Koshland, "Identification of a Lymphocyte Enzyme That Catalyzes Pentamer Immunoglobulin M Assembly," Journal of Biological Chemistry, (1981) 256(9):4633-9. Polymerization of IgA is also initiated by J chain assembly. IgA molecules exist predominately as dimers and are not believed to utilize any other enzyme systems for further polymerization. Thus, homopolymers of monomer IgM or IgA are assembled in vivo via the cysteine residue near the carboxyl terminal end. The disulfide bonds at this position covalently link the monomers.
This invention presents a methodology for chemically linking carboxyl-terminal sulfhydryl residues of monoclonal antibodies to form hybrid molecules. These hybrid molecules are defined in the preferred embodiment as an antibody of the IgM or IgA class linked to another component including an antibody, enzyme, hormone, toxin or carrier protein (a protein which acts only as a delivery and amplification system for smaller molecular weight components) in which the carrier protein may contain a suitable labeling agent or a suitable cytotoxic agent.
2. Description Of The Prior Art | {
"pile_set_name": "USPTO Backgrounds"
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The invention relates to an electromagnetically operated valve construction wherein permanent-magnet action is effective to latch, i.e., to retain, a selected open or closed condition of the valve.
U.S. Pat. No. 3,814,376 describes a magnetically operated two-position latching valve having an armature that also serves as a movable valve element, with valve action, and inlet and outlet flow connections, all at one axial end of the construction. The armature is movable to its two positions by and is latched in one or the other of its two positions solely by magnetic flux. An elongate armature is actuated from one to the other of its positions by excitation of two solenoid coils in a first polarity relationship, and return from said other to said one position is effected by excitation of the two solenoid coils in a second or reversed polarity relationship. The armature is a relatively massive cylinder which is guided in an elongate bore; it is therefore subject to friction which can become a source of unreliable operation, in the event of grit or other particles which may be borne by fluid controlled by valve action. The mass of the armature also makes the construction vulnerable to an inertial response to mechanical shock, wherein an unwanted open-valve condition is an inadvertent occurrence, or wherein an open-valve condition is inadvertently shut down. | {
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Surface plasmons are coherent electron oscillations that exist at the interface between any two materials where the real part of the dielectric function changes sign across the interface (e.g., a metal-dielectric interface). When surface plasmons couple with an incident photon, the resulting hybridized excitation is called a surface plasmon polariton (SPP). Therefore SPPs are bound electromagnetic modes that can occur at metal-dielectric interfaces and correspond to polarization waves of free electrons in the metal. Therefore, electromagnetic modes can propagate along a bare metal surface and decrease exponentially in the perpendicular direction, thereby strongly confining light to the surface until energy is lost either via absorption in the metal or radiation into free space.
An optical grating is formed by a periodically modulated interface between a dielectric and a metal. It is well known that at such structured surfaces, the absorption may strongly depend on the angle of incidence and the polarization of the incident light. Therefore, in angular reflectivity measurements, minima are observed at specific angles of incidence that are attributed to the incident light being transformed into a SPP wave which dissipates the energy in the metal, finally being converted to thermal energy. Conversely, if the thermal energy of the metal is high enough to populate surface plasmon states, the grating can transform these excitations into plane electromagnetic waves leaving the surface, leading to a maximum in emission observed near the angle at which the minimum of reflectivity is observed in the reflectivity measurement, as expected according to Kirchhoff's law of thermal radiation. Specifically, surface waves that are excited by heating the metal are diffracted by the grating in directions for which the condition of phase matching is met as a result of some spatial coherence in the surface plane. Therefore, the absorption and emission spectra can be highly directional and of a narrow bandwidth defined by the symmetry and periodicity of the surface structure for a given wavelength.
Surface plasmons in the mid-wave and long-wave infrared (LWIR), nominally 3-15 μm, have notable differences to plasmons in the visible and near-infrared part of the electromagnetic spectrum. Two defining characteristics of SPP modes are the propagation length, δspp, and the dielectric surface penetration depth, kd. These features are directly proportional to one another over all frequency ranges, but exist in opposite extremes for the visible and infrared (IR), with propagation length and dielectric penetration being small in comparison to wavelength in the visible, and quite large in the infrared. These physical properties of the LWIR SPP's have made it a challenge to find efficient applications in this frequency range, though some have been demonstrated. See C. Sirtori et al., Opt. Lett. 23, 1366 (1998); and N. Yu et al., Nature Photonics 2, 564 (2008). For example, performance of the quantum cascade laser (QCL) has been improved through the use of SPP waveguide modes, while the beam profile and polarization state of mid-IR QCL's have been modified using SPP's as well.
However, for further applications to be developed, a need remains for long-wavelength plasmons that can be generated with the high confinement and high loss of conventional SPP's. One potential application of long-wavelength plasmons is directional emission, where plasmon radiation loss can be beneficial. Careful design of a periodic surface structure can allow the emission (absorption) to occur only over a narrow angular range. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to an excited frame vibratory conveying apparatus for conveying objects thereon.
Carmichael, U.S. Pat. No. 4,313,535, incorporated by reference herein, discloses an excited frame vibratory conveyor that includes an elongated conveying member mounted by beam springs on an excited frame. The excited frame has a balanced vibratory drive for vibrating the excited frame along a line of force that passes through the center of masses of the conveying member and the excited frame. The balanced vibratory drive includes a pair of counter-rotating masses that provide a resultant vibratory force. The basic objective of such a system is to maintain the vibration amplitude of the excited frame at zero while the conveying bed or member is vibrated near its natural frequency of maximum amplitude. The generally recognized advantages of such a system, over conventional direct vibratory conveyors where the vibratory drive is connected directly to the conveying member, is that under some conditions it is possible to transfer less vibration into the floor or ceiling supports and to provide a conveyor that is considerably less massive than the direct drive systems. Carmichael also teaches that the stroke of the conveying member may be controlled by changing the rpm of the vibratory drive. Consequently, it is possible to adjust the stroke of the conveying member by changing the speed of rotation of the vibratory drive.
Unfortunately, the conveyor system taught by Carmichael experiences significant transient vibrational motion of the excited frame and conveying member during start up and shut down of the conveyor system. It is during these periods of transition that significant vibrational forces are transferred into the floor or ceiling supports which may result in catastrophic failure, such as the conveyor system becoming dislodged from its supports. During normal operation product is added to one end of the conveying member at the same rate as it is being discharged from the other end of the conveying member. However, it has been observed that when excess product is added to the conveyor system taught by Carmichael, the system will experience catastrophic failure, such as transferring significant vibrational forces into the floor or ceiling supports, bouncing the excited frame on its supports, and failure of the conveyor system to convey products. In order to prevent such a potentially catastrophic failure, the conveyor system is normally designed to operate at a point less than its maximum efficiency in the event that excess product is added to the conveying member. Carmichael also teaches the use of such an operating point by including only one-third of the weight of the anticipated particulate material in the calculations to determine the loaded center of mass of the elongated conveying member. Unfortunately, operating the conveyor system at such an operating point is less efficient than operating the conveyor system at its resonant frequency.
Frolich et al., U.S. Pat. No. 5,127,512, disclose an electromagnetically driven vibrating conveyor system that operates with a constant excitation frequency. The conveyor system is a dual-mass system, namely, the mass of an electromagnetic drive and the mass of the conveyor itself to which the drive is directly connected thereto. The electromagnetic drive regulates the amplitude of the vibration during operation at different loading conditions. Unfortunately, such a dual-mass system transfers substantial vibrational forces into the floor or ceiling supports and tends to be more massive in comparison to the excited frame system taught by Carmichael. Further, the electromagnetic drive is typically more expensive and complicated than the traditional counter-rotating mass drive, as taught by Carmichael. Bertrand, U.S. Pat. No. 4,088,223, and Fishman et al., U.S. Pat. No. 5,213,200, also disclose direct drive vibratory conveyors.
What is desired, therefore, is an excited frame vibratory conveyor that eliminates the transients occurring during start-up and shutdown, and also operates at maximum efficiency. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a printing medium conveying device and an image forming apparatus.
2. Description of the Related Art
In conventional image forming apparatuses, sheets such as documents and recording sheets are sequentially conveyed by a printing medium conveying device from a paper cassette to a sheet ejection unit. The printing medium conveying device includes a conveying path including a plurality of guiding members and a plurality of rollers that are driven to rotate, through which sheets are conveyed.
Once a printing operation is started, toner images formed in four colors (yellow, magenta, cyan, and black) image carriers are transferred to an intermediate transfer belt. Sheets that have been fed from the paper cassette one by one are conveyed through the conveying path to a secondary transfer device, where the toner images on the intermediate transfer belt are transferred to the sheet. The toner images are then fixed to the sheet in a fixing unit, and after that the sheet is ejected from the printing medium conveying device to outside the apparatus.
A skew correction device is provided in the conveying path for correcting the skew of the sheet occurred during the conveyance. The skew correction device abuts the leading edge of the sheet to the guiding member to align the position of the leading edge of the sheet to correct the position of the sheet so as to be parallel to a secondary transfer device. Specifically, by feeding the sheet excessively between a roller for the skew correction and a conveying roller located in the upstream thereof, the leading edge of the sheet is abutted to the guiding member. To align the sheet as described above, a space is required for forming slack on the sheet that has been fed due to evacuation of the sheet from the conveying path. For that purpose, sufficient distances and spaces need to be ensured between the rollers. In addition, if the used sheet is more rigid and thicker, larger distances between the rollers need to be ensured.
In recent years, however, the need has increased for a printer and other image forming apparatuses to cope with various types of sheet, print on a rigid thick sheet and print on a short-sized sheet such as a post card with a single printer or apparatus.
When slack is formed on a sheet between rollers using a skew correction device, for example, if the rollers are arranged with a short distance interposed therebetween, the conveying roller cannot feed a rigid thick sheet excessively due to the hardness of the sheet. To address such an issue, as disclosed in Japanese Patent Application Laid-open No. 2008-024507, for example, a mechanism is provided to separate a pair of rollers in the vertical direction and convey the sheet using other conveying rollers provided on the upstream thereof. With this structure, the sheet does not contact with the separated rollers, whereby slack is formed on the sheet along the long pitch between the upstream rollers and the rollers for the skew correction. The separation operation of rollers is performed, however, in a short time and typically for a few millimeters. The separation distance is too short to ensure a space to form sufficient slack on the sheet, causing an obstacle for feeding the sheet.
In view of the circumstances above, there is needed to provide a printing medium conveying device capable of ensuring a space for feeding sheets of different lengths to correct the direction of the sheets when printing media are conveyed. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates generally to cyclonic separators. In one particular application, the invention relates to the cyclonic separation of particulate material from an air flow.
The use of a cyclone, or multiple cyclones connected in parallel or series, has long been known to be advantageous in the separation of particulate matter from a fluid stream. Typically, a relatively high speed fluid stream is introduced tangentially to a generally cylindrical or frusto-conical container, wherein the dirty air stream is accelerated around the inner periphery of the container. The centrifugal acceleration caused by the travel of the fluid in a cyclonic stream through the cyclone causes the particulate matter to be disentrained from the fluid flow and, eg., to collect at the bottom of the container. A fluid outlet is provided for the extraction of the fluid from the centre of the top of the cyclone container, as is well known in the art.
A typical flow path in a cyclone separator is as follows. Fluid to be treated is introduced tangentially at a fluid inlet located at an upper end of the cyclone container. The fluid stream rotates around the inner surface of the cyclone container, and spirals generally downwardly around the inner surface of the container (if the cyclone container is vertically disposed). At a bottom end of the cyclone container the fluid stream travels radially inwardly, generally along the bottom of the container and then turns upwardly and proceeds vertically up and out of the cyclone container. The particulate matter separating action of the cyclonic flow occurs substantially around the inner surface of the container. Once the fluid moves inwardly to the centre of the container, and upwardly there through, there is little or no dirt separation achieved.
The difficulty experienced with prior art cyclonic separators is the reentrainment of the deposited particles back into the outgoing fluid flow. Deposited particles exposed to a high speed cyclonic flow thereover have a tendency to be reentrained. This is particularly problematic when the container has a solid bottom portion in which the dirt collects. However, there is a potential reentrainment problem even if the bottom of the container has a passageway provided in the bottom thereof to convey the separated particulate material away from the container.
If a high degree of separation is required, it is known to connect a plurality of cyclones in series. While using several cyclones in series can provide the required separation efficiency, it has several problems. First, if the separators are to be used in industry, they generally need to accommodate a high flow rate (eg. if they are to be used to treat flue gas). The use of a plurality of cyclones increases the capital cost and the time required to manufacture and install the separators. Further, the use of a plurality of cyclones increases the space requirements to house the cyclones. Accordingly, there is a need for an improved anti-reentrainment means for cyclonic separators.
In has now been discovered that a single cyclone having improved efficiency (eg. up to 99% efficiency) may be manufactured by positioning in the cyclone chamber a member for creating a dead air space below the cyclonic flow region of the cyclone chamber. This construction traps separated material below the cyclonic flow region and inhibits the reentrainment of the separated material. Thus, a single cyclone may be used in place of a plurality of cyclones to achieve the same separation efficiency.
In accordance with the instant invention, there is provided a separator for separating entrained particles from a fluid flow, the separator comprising a cyclone chamber having a cyclonic flow region, the cyclonic flow region having a center, a longitudinal axis, an outer peripheral portion, an inner portion and a radial width; a fluid inlet for introducing a cyclonic fluid flow to the cyclonic flow region; a fluid outlet for removing the fluid flow from the cyclone flow region; a plurality of vanes positioned in the cyclone chamber and extending inwardly towards the center, the vanes having an inner portion and an outer portion and creating a dead space; and, a cover member spaced from the bottom and positioned above the vanes.
In one embodiment, the separator has a bottom and the vanes are spaced from the bottom whereby the dead zone is positioned beneath the vanes.
In another embodiment, the separator has an open end distal to the fluid inlet and the vanes are spaced from the open end whereby the dead zone is positioned beneath the vanes.
In another embodiment, the cover member is positioned over the inner portion of the vanes. The cover member may have a radial width that is from 25-75% and preferably from 25-35% of the radial length of the vanes.
In another embodiment, the vanes extend downwardly from the cover member. The vanes may have a height of at least three-quarters the distance between the bottom and the cover member. Preferably, all of the vanes are of substantially the same height. Further, preferably the vanes are substantially parallel to the longitudinal axis.
In another embodiment, the vanes extend upwardly at an angle of up to 45xc2x0 to the longitudinal axis.
In another embodiment, the vanes are equidistantly spaced around the bottom.
In another embodiment, the vanes extend to the centre and the cover member has a radial width that is from 25-35% of the radial width of the cyclonic flow region.
In another embodiment, the vanes curve in the downstream direction as they extend inwardly from the outer periphery.
In another embodiment, the vanes extend radially inwardly from the outer periphery.
In another embodiment, the separator further comprises a cleaner head adapted for movement over a floor and having a fluid nozzle positionable adjacent the floor, the nozzle in fluid flow communication via a passageway with the separator fluid inlet, a handle for moving the cleaner head over the floor, and a casing for housing the cyclone chamber. The separator may further comprise a centre feed pipe, the vanes extend to the centre feed pipe and the cover member extends outwardly from the centre feed pipe, the cover member having a radial width that is from 25-75% of the radial length of the vanes.
In accordance with the instant invention, there is also provided a separator for separating entrained particles from a fluid flow, the separator comprising a cyclone chamber having a cyclonic flow region, the cyclonic flow region having a center, a longitudinal axis, an outer peripheral portion, an inner portion and a radial width; means for introducing a fluid flow to the cyclone flow region for cyclonic rotation therein; separations means for creating a plurality of non-rotational flow regions positioned beneath the cyclonic flow region; particle receiving means disposed beneath the separations means for receiving particles separated from the fluid flow; and, means for removing the fluid flow from the cyclone flow region positioned above the particle receiving means.
In one embodiment, the cyclone chamber has a bottom spaced below the separation means and the particle receiving means is positioned between the bottom and the separation means.
In another embodiment, the separator further comprises means for removing particles separated from the fluid flow from the cyclone flow region positioned below the separations means.
In another embodiment, the separation means comprises cover means positioned in the inner portion of the cyclonic flow region and baffle means extending in the direction of the longitudinal axis of the cyclonic flow region and extending downwardly from the cover means.
In another embodiment, the baffle means are generally parallel to the longitudinal axis. | {
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As the capacity of semiconductor memory continues to increase, attaining a sufficiently high yield becomes more difficult. To attain higher memory capacity, the area of a memory chip can be increased to accommodate a greater number of memory cells. Alternately, the density of the chip can be increased. Increasing the density involves reducing the size and increasing the quantity of memory cells on the chip, which leads to a proportional increase in defects.
To improve the yield, a number of techniques may be employed to fix or to compensate for the defects. A relatively expensive technique that is commonly used for repairing standard memory chips is a wafer test, sort and repair process. The capital equipment costs for burn-in and test facilities are relatively high, which can be amortized when the standard memory chips are produced in sufficiently large quantities. For lower production quantities, the amortized capital equipment costs often exceed the cost of scrapping the defective chips.
Embedded memory devices also face problems with attaining sufficient chip yield. Embedded memory devices combine logic and memory on a single silicon wafer and are not usually manufactured in large quantities. The wafer sort/test fixtures, burn-in fixtures, and repair facilities that are typically used with large quantity standard memory devices are not economically feasible. When a defect occurs on an embedded device, the device is typically scrapped.
Embedded devices typically have more defects per unit of memory than standard memory. This is due in part to the fact that the processing technology that is used for the logic is typically not compatible with the processing technology that is used for the memory. The majority of defects in an embedded device occur in the memory since most of the chip area is used for the memory. Typically, the prime yield is about 20% for conventional logic devices.
Referring now to FIG. 1, systems on chip (SOC) 10 typically include both logic 12 and embedded memory 14 that are fabricated on a single wafer or microchip. For example, the SOC 10 may be used for a disk drive and include read channels, a hard disk controller, an Error Correction Coding (ECC) circuit, high speed interfaces, and system memory. The logic 12 may include standard logic module(s) that are provided by the manufacturer and/or logic module(s) that are designed by the customer. The embedded memory 14 typically includes static random access memory (SRAM), dynamic random access memory (DRAM), and/or nonvolatile memory such as flash memory.
Referring now to FIG. 2, low chip yield is due in part to the small size of the memory cells in the embedded memory 14. The small memory cells are used to reduce the chip size and lower cost. Typical defects include random single bit failures that are depicted at 16. For a 64 Mb memory module, on the order of 1000 random single bit failures 16 may occur. Other defects include bit line defects that are depicted at 18 and 20. While bit and word line defects occur less frequently than the random single bit failures 16, they are easier and less costly to fix.
Referring now to FIG. 3, the embedded memory 14 typically includes a random data portion 24 and a cache data portion 26. Bits that are stored in the random data portion 24 are accessed individually. In contrast, bits that are stored in the cache data portion 26 are accessed in blocks having a minimum size such as 16 or 64 bits.
To improve reliability, an error correction coding (ECC) circuit 28 may be used. ECC coding bits 30 are used for ECC coding. For example, 2 additional bits are used for 16 bits and 8 additional bits are used for 64 bits. The ECC circuit 28 requires the data to be written to and read from the embedded memory 14 in blocks having the minimum size. Therefore, the ECC circuit 28 and error correction coding/decoding cannot be used for the random data portion 24. When accessing the random data portion 24, the ECC coding circuit 28 is disabled as is schematically illustrated at 32. ECC coding bits also increase the cost of fabricating the memory and reduce access times.
Because each of the bits in the random data portion 24 can be read individually, single bit failures in the random data portion 24 are problematic. During the wafer sort tests, if single bit failures are detected in the random data portion 24, repair of the SOC 10 must be performed, which significantly increases the cost of the SOC 10. | {
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Along with the recent development of high-density and highly integrated electrical and electronic components, there exists a demand for improvement of the reliability of these components.
In particular, not only a moisture-proof property at room temperature but also high reliability even in a high-temperature and wet-heat environment is required of electrical and electronic components used in vehicle engines, water heaters, etc.
For the purpose of protecting such electrical and electronic components from moisture, dust-containing atmosphere, vibration, impact, etc., electrically insulating sealing members have been used. Flexible resins that have low hardness, e.g., silicone-based resins and urethane-based resins, have typically been used as materials for such sealing members.
Silicone-based resins are excellent in heat resistance, flexibility, and low-temperature characteristics. However, silicone-based resins are not necessarily satisfactory in adhesion to materials of electrical components, and the moisture permeability is high. Thus, silicone-based resins are disadvantageous in that the influence of water cannot be fully avoided.
On the other hand, urethane-based resins are inherently excellent in flexibility, abrasion resistance, low-temperature curability, electrical characteristics, and the like, and are thus used for electrically insulating sealing members.
MDI (diphenylmethane diisocyanate) is typically used as an isocyanate component of urethane-based resins. Such urethane-based resins are often poor in heat resistance. Thus, unfortunately, when such urethane-based resins are used as a sealing member of an electrical component, particularly in a severe environment (e.g., in the vicinity of an engine), cracks are likely to appear on the surface of the sealing member over time, and the electrical component cannot be protected from moisture over a prolonged period of time.
As a heat-resistant polyurethane resin composition for electrical components, there have been proposed, for example, aliphatic and/or alicyclic polyurethane resins for sealing solar cells that are electrically connected on a panel (see Patent Document 1).
However, an analysis of the compatibility between the polyisocyanate component and the polyol component is not conducted in Patent Document 1. An isocyanurate ring-containing polyisocyanate has poor compatibility with a polyol component. Thus, the polyurethane resin composition proposed in Patent Document 1 has a drawback in that, when the polyurethane resin composition is used, the resulting cured molded article becomes sticky; and adhesion to an object becomes weak, which leads to a decrease in moisture resistance and insulation properties.
As a heat-resistant polyurethane resin composition in which a polyisocyanate component is compatible with a polyol component, Patent Document 2 proposes a polyurethane resin composition comprising a polybutadiene polyol (A) and a castor oil-based polyol (B) as hydroxyl-containing compounds, and a modified isocyanurate (c) of a polyisocyanate compound as an isocyanate-containing compound. Patent Document 3 proposes a polyurethane resin composition that is obtained by reacting a polyisocyanate (A) with a polybutadiene polyol (B), wherein the 1,2-vinyl structure content in the polybutadiene polyol (B) is more than 85 mol %.
However, in both Patent Documents 2 and 3 as well, an analysis of the polyisocyanate component for obtaining a polyurethane resin composition excellent in compatibility is not fully conducted. Due to the insufficient compatibility between the polyisocyanate component and the polyol component, it cannot be said that heat resistance, moisture resistance, and insulation properties are satisfactorily achieved in the use of such polyurethane resin compositions for electronic components. Therefore, to be suitably used for various electrical components, these polyurethane resin compositions remain to be improved. | {
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Deafness and balance dysfunction are common human disabilities. In the majority of cases these disabilities result from the loss of sensory hair cells in the (1) organ of Corti (OC) in the cochlea, (2) the vestibular epithelium in the cristae or (3) saccule or utricle of the vestibular organ. Currently there is no FDA approved treatment that can cure these disorders by restoring the sensory hair cells in these tissues.
Current approaches to the problem involve vestibular rehabilitation to allow adaptation to the injury to the vestibular organs. The rehabilitation is time consuming, and does not restore lost function. For sensorineural deafness, rehabilitation can be achieved with hearing aids or cochlear implants. However, these devices are expensive, require an extensive surgery and produce a subnormal sound quality and only partial return of function.
Another approach in treating hearing disorders is administration of peptides or other small molecules. Often treatment results are limited with the use of such due to relatively high cochlear concentrations that must be achieved (micro or millimolar). Moreover, protein or peptide inhibitors are difficult to deliver systemically to treat the ear due to the blood labyrinthine barrier and protein clearance in the bloodstream as well as potential antigenicity. Difficulties also exist in terms of delivering adequate concentrations of peptide and protein directly to the cochlea as well, particularly using topical delivery due to the size of the molecule.
One potential alternative to these traditional approaches is using targeted gene therapy to induce inner ear hair cell regeneration and replacement. For example, hair cell regeneration or replacement has been achieved in rodents through the use of a viral vector to introduce the Atoh1 gene into inner ear sensory epithelium. However, this approach carries risk inherent in viral vector therapy including the induction of infection, an inflammatory immune response, genetic mutation, development of neoplasia and others. Silencing of kip1p27 RNA has been shown to induce hair cell regeneration but in an ectopic fashion without return of function. Modulation of the retinoblastoma gene can also produce additional hair cells but there may be danger inherent in manipulating an oncogene, or cancer causing gene. Thus, current gene therapies directed to regeneration or replacement of inner ear hair cells have failed to identify a safe and effective molecular target and delivery method.
One potential gene therapy approach is through the use of short interfering RNA (siRNA). Once introduced into a cell, the siRNA molecules complex with the complimentary sequences on the messenger RNA (mRNA) expressed by a target gene. The formation of this siRNA/mRNA complex results in degradation of the mRNA through a natural intracellular processes known as RNA interference (RNAi). RNAi is a well-established tool for identifying a gene's function in a particular cellular process and for identifying potential therapeutic targets in disease models. Although RNAi has traditionally been used in cell culture and in vitro applications, gene-therapy based therapeutics are now being explored utilizing this process.
As discussed above, several gene targets have been explored with respect to regeneration of hair cells of the inner ear without much success. The basic helix-loop-helix (bHLH) genes Hes1 and Hes5 have been identified as playing roles in sensory hair cell development in the cochlea and vestibular structures of the ear. In addition, a potential gene target for preventing loss of hair cells is mitogen-activated protein kinase 1 (MAPK1), which plays a role in programmed cell death or apoptosis. However, the potential for these to be effective therapeutic targets for regeneration or protection of sensory hair cells of the inner ear has yet to be demonstrated and or identified as a viable approach. | {
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This invention is in the art of sewing machines, relates to devices for forming chain stitches in a novel and advantageous manner, involves combinations with chain stitch mechanism heretofore unattainable, and more particularly, provides for a novel arrangement which may be used in a lock stitch machine for converting the mechanism to the production of chain stitches.
Many chain stitch mechanisms and chain stitch conversion devices are known in the prior art that operate by retaining a thread loop until it has been entered by the needle on the succeeding needle penetration. All of the prior art devices further share in common the attribute that shedding of the retained thread loop is effected as the result of a movement of a part of the sewing machine mechanism which is not necessarily related to the actual seizure and manipulation of the succeeding loop of thread. As a result, if for any reason loop seizure should fail to occur, the previously formed thread loop will be released without being enchained and the resulting interruption of the chain of loops can permit the seam to be raveled.
The U.S. Pat. of Bartosz No. 3,173,390, Mar. 6, 1965, is representative of the prior art and discloses a chain stitch forming conversion device for a lock stitch sewing machine in which a web on the sewing machine feed dog, during the recurring motion of the feed dog, engages and strips the retained thread loop from a thread loop retaining finger. In the mechanism of U.S. Pat. No. 3,173,390, the thread loop will be shed from the thread retainer whether or not the loop taker beak is successful in seizing the succeeding thread loop from the needle. | {
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This invention relates to compositions comprising an edible oil, especially to powdered compositions; to methods of producing these compositions; to food products comprising these compositions; and to the use of the compositions.
Edible oils that contain unsaturated fatty acids, and especially polyunsaturated fatty acids (PUFA), usually in the form of glyceride esters, have been shown to have beneficial health effects. These health effects include reduction of cholesterol levels, protection against coronary heart disease and suppression of platelet aggregation. For example, fish oil, which contains the omega-3 and omega-6 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), has been used in food products and in nutritional products for its health benefits.
PUFA have been incorporated into a matrix. For instance, WO 97/37546 discloses free flowing compositions comprising a fat blend. As a further example, EP-A-1175836 discloses edible fat based flakes containing a fish oil.
One problem with PUFA is that they have a tendency to undergo oxidation and as a result can have an unpleasant taste and/or odour. This tendency also has a negative effect when the PUFA are stored; that is, the shelf or storage stability is relatively short because of the problems associated by the tendency to undergo oxidation.
Conventional powdered fish oils have therefore been treated in a specific way and/or incorporated agents that stabilise the PUFA against oxidation.
For example, WO-94/01001 discloses a microencapsulated oil or fat product on the basis of caseinate as the encapsulating compound. The use of caseinate as the only emulsifying agent optionally in combination with at least one carbohydrate results in relatively stable oil or fat products.
U.S. Pat. No. 3,971,852 describes a process wherein the use of polyhydroxy alcohols as a component within a micro encapsulating matrix can be beneficial to the final powder characteristics of the formed product. A lower surface area and less powder surface discontinuities are a result of this process. However, no special remarks have been made to a better oxidative shelf life of the hereby-obtained products.
U.S. Pat. No. 5,972,395 describes the combination of a minor part of a high molecular weight and a major part of a low molecular weight component within the encapsulating matrix for use in an extrusion process. The low molecular weight component can consist of low melting water soluble carbohydrates, sugar alcohols, adipic acid, citric acid, malic acid, and combinations thereof. However, no specific preference for any of these combinations has been made in respect to enhanced oxidation stability.
The stabilisation of aqueous emulsions containing fish oil using raffinose, trehalose or sorbitol together with a metal ion chelator is disclosed in U.S. Pat. No. 4,963,385. Stable liquid mineral ascorbate compositions and methods of manufacture and use are described in U.S. Pat. No. 6,197,813. The obtained liquid compositions are stabilised against oxidative degradation by the presence of sugar alcohols, sugars, or a metal ion chelator, or combinations thereof. WO 89/02223 describes the use of fructose for the stabilisation of emulsions containing fish oils, such as salad dressings.
It has also been suggested to stabilise fish oil with cyclodextrin, see, for example, U.S. Pat. No. 4,438,106. In a further development, U.S. Pat. No. 6,638,557 seeks to reduce the amount of cyclodextrin that is used in a composition containing an edible oil and starch by employing a converted starch and a starch hydrolysate in the composition. The starch hydrolysate is a maltodextrin or a thin boiled starch. These components can increase the viscosity of the composition before it is processed into a powder. This increase in viscosity can be a disadvantage in powder production.
It is known that some simple carbohydrates are potential hydroxyl radical scavengers in liquid compositions. See in this respect Int. J. Food Sciences and Nutrition, 2002, 53, 419 423 and J. Agric. Food Chem., 2003, 51, 7418-7425.
Further examples of conventional powdered fish oil containing agents that stabilise the PUFA against oxidation are described in JP-A-8-259944. This document discloses the use of sugar alcohols, such as mannitol, as oxidation stabilisers for emulsified oil or fat. Similar disclosures can be found in JP-A-8-259943 and JP-A-8-051928.
However, various disadvantages are to be expected employing the oxidative stabiliser as described in JP-A-8-259944. For instance, the high amount of mannitol, being a sweetener, within the described compositions can negatively affect the taste.
Furthermore, sugar alcohols such as mannitol are known for their laxative effect. Initial laxative threshold of mannitol varies between 20-40 g/day, although the accepted daily intake (ADI) of mannitol has not yet been specified by WHO (1987). The use of mannitol as described in the JP-A-8-259944 application to stabilise emulsified oil or fat is from an economical point of view also not preferred. The associated costs of polyols, e.g. mannitol, put limitations on the use according to JP-A-8-259944. Essentially, the use of mannitol in the way as taught in the prior art is disadvantageous because of both the cost issue and the limitations associated with laxative effects. These two disadvantages associated with the use of mannitol are even more profound when mannitol is used with the intention to increase the stability and shelf life of compositions containing low cost oils such as linseed oil, soya oil, sunflower oil or rapeseed oil. These type of compositions are generally used in relatively large quantities as a food ingredient in numerous food applications, generally consumed in relatively large amounts. | {
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This invention relates to devices for overcoming male impotence and more particularly to a device applied externally to the shaft of the penis that inflates to constrict the shaft to enhance rigidity.
With advancing age, and also in certain pathological conditions, men may not be able to achieve an erection with sufficient rigidity for satisfactory coitis. Various devices of the prior art for overcoming the problem are surgically implanted within the penis. Some are permanently rigid and hinged. Others provide a flaccid inflatable chamber which becomes rigid when inflated with fluid. The inflating apparatus is also implanted within the body. These invasive procedures destroy normal tissue, they are attended by the usual surgical risks, such as infection and hemorrhage, and they are not always successful. There is little chance of restoring normal function when they are removed.
There is no way to temporarily try the devices to predict success following the operation. It is devastating to go through the expense, trauma, and risk of an irreversible procedure and then find out that it does not improve function. It is also discouraging to the physician to deal with the dissatisfied patient for whom he has recommended the procedure. Non surgical treatments includes use of a vacuum chamber to expand the penis followed by a constrive cuff at the base.
U.S. Pat. No. 4,407,275 issued Oct. 4, 1983 to Schroeder discloses a semi rigid annular ring having individual expandable chambers on the internal wall that is applied to the outside of the penis. A multiple lumen flexible conduit connected to the ring has individual connections for each chamber connecting to a pressure bulb and valve arrangement remote from the device for expanding and contracting the chambers in sequence in a wave fashion to allow only one chamber at a time to be pressurized, sending pressure down only one of the lumens at a time. This is a cumbersome, and complex apparatus which may allow blood to pass back to the heart while a chamber is being depressurized. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a process for preparing di-amino-polyalkenyl eithers, including those which are severly sterically hindered by reacting (a) an acyclic primary or secondary amine or a heterocyuclic amino compound with (b) a polyalkenyl either glycol or a polyalkenyl amino either alcohol, in the presence of a hydrogenation catalyst at elevated temperatures and pressures. The resulting di-amino-polyalkenyl eithers are useful in acid gas scrubbing, particularly in the selective removal of H.sub.2 S from gaseous streams containing CO.sub.2 and H.sub.2 S.
2. Description of Related Patents and Publications
Recently, it was shown that di-severely sterically hindered amino-polyalkenyl-ethers are superior agents for scrubbing H.sub.2 S from gaseous streams containing the same, especially in selectively removing H.sub.2 S from normally gaseous mixtures containing CO.sub.2 and H.sub.2 S. Such processes are disclosed in U.S. Pat. Nos. 4,405,482 and 4,405,583, both incorporated herein by reference. The art teaches that these compounds may be prepared by reacting the appropriate primary amine with a bis-(haloalkoxy)alkane or bis-sulfonate ester of a glycolic ether under conditions such that the haloacid or sulfonic acid is eliminated. This process is more fully disclosed in allowed U.S. Ser. No. 339,899 filed Jan. 18, 1982, the disclosure of which is incorporated herein by reference. Disadvantages of such processes include relatively expensive raw materials and product isolation. That is, the initially formed product is an amine salt which requires caustic treatment as a part of the product isolation procedure.
Consequently, there exists a need in the art for methods of preparing di-severely sterically hindered amino-polyalkenyl ethers which would not be limited by such disadvantages. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention is related to a method and system for distribution of software related information that is required for running the software in different execution environments.
2. Related Art
Frequently, there are three types of software that are installed on a computer system. The first is the operating system itself. The second is application software that is normally loaded with the operating system (for example, when the hard disk drive is installed by the original equipment manufacturer, or OEM). The third is third party application software, such as games, database packages, third party word processors, etc., that is installed by the user subsequent to purchasing the computer.
Consider a certain application that is currently running on a computer. It may be necessary to supervise behavior of a component of that application, e.g., to perform a patching of the code of this application, depending on the run-time conditions of the installed third party component that behaves in an unforeseen manner, e.g., shared components of the application or components that result from application execution. In other words, the file itself that is stored on some storage media (such as a disk drive) needs to be patched, or the code that is loaded into memory or produced during execution needs to be patched, shared, or processed in some unforeseen manner. In order to accomplish this, it is necessary to know additional information related to the application for executing appropriate patching or modification of application behavior in a safe manner.
Such information may be addresses or offsets of the functions (or pieces of code) that are being patched. Another kind of information may be system settings such a registry settings provided during execution of the installed component. Also descriptions of file trees of even files may be unintentionally hidden or absent, or such information can depend on the environment where the installed component is running.
Conventionally, the user cannot readily retrieve such information. For example, the code of the application needs to be disassembled, and using a relatively complex process, offset addresses in some cases can be determined. This is frequently difficult and can run into a problem of violating either the copyright of the owner of the application software, or the license that is associated with that software. Also, even with sophisticated algorithms for reverse assembly, determination of the offset addresses of the relevant functions is not always possible.
Also, if the user has to configure auto-configured software in a specified manner, e.g., for execution of a software component in a virtual environment, such a task may be non-trivial, since some virtual environment runtime objects, properties or configurations might not be recognized by auto-configuration mechanisms.
Accordingly, there is a need in the art for producing and distribution of the information related to the installed software component that is unintentionally hidden or strictly unrecoverable, for the purpose of modifying the behavior of the installed component, or monitoring its behavior. | {
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The present invention relates to a method for coating live worms which may be earthworms, seaworms or the like.
A prior art search uncovered the following U.S. Pat. Nos. 2,749,647; 3,421,899; 3,545,404; 3,931,414; 3,953,934; 3,987,575 and 4,053,640. Some of these prior art patents such as Beloff disclose artificial lures which have their attraction to fish enhanced by the addition of fish-attracting substances. The Beloff patent shows an artificial lure having an open cavity containing a finely divided material such as lobster meat, soy bean, cotton seed oil, etc. The Morita patent and the Visser patent also show different materials that may be used in association with an artificial lure. The Takasugi and Popeil patents suggest the use of pulverized fish bait of various types of materials such as, for example, raw fish. These patents suggest the application of this material directly onto the hook. However, none of the prior art that was found suggest a mixture in accordance with the present invention and which is to be coated directly on a live earthworm or seaworm.
The patent to Loftus discloses the treatment of live worms but only for the purpose of making them irridescent. Again, this patent does not disclose nor suggest the principle of the present invention of coating live worms for facilitating ease in handling these worms for baiting them onto a hook.
In accordance with the present invention there is provided a material for coating bait which is preferably used for coating live bait to facilitate the handling of the bait to primarily make it easier to put the bait onto a hook. This material is preferably made from a powdered wood flour which is applied to the bait such as earthworms so as to make it easier to handle and hold the bait when it is being put onto a hook. It has been found that the baiting process is accomplished quite rapidly with the technique of this invention. Hooks can be baited as much as five times faster using the technique of this invention in contrast to the prior way of simply hooking the earthworm onto the hook. The wood flour is preferably made from a hardwood tree with the preferred hardwoods being maple and birch. It is also preferred that the wood flour be mixed with dehydrated ground food product such as powdered earthworms, mussels, shrimp, clams or the like. In accordance with the method of this invention it is practiced by applying the powdered wood flour to the bait to enhance the gripping of the bait. In the conventional method of baiting an earthworm, the earthworm is usually difficult to hold stationary, however, with the method of this invention by applying the powdered wood flour the bait can be handled much more easily. The powdered wood flour may be applied with the use of a shaker to shake the material on to the bait or it may be applied by dipping or rolling the bait in the material. | {
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This invention is related to the field of electronically controlled devices, and more particularly to a video recording device.
A video cassette recorder (VCR) is typically coupled to an incoming cable service port and to a television set. A conventional VCR provides a user with the ability to perform two major functions: recording incoming television programs from the cable service port and playing videotapes for viewing on the television. The videotapes that are played can be, for example, tapes of television shows previously recorded by the VCR, professionally produced movies purchased or rented by the user, or recorded tapes produced by the user on a camcorder.
A feature typically available on a VCR provides its user with the ability to program the VCR to record a television show at a future date and time. Further, some VCRs can be programmed to record at regular intervals, such as at the same time each week in order to record the user""s favorite television show. For example, a user can program such a VCR to record the television show appearing on channel 4 each Thursday from 9:00 p.m. to 10:00 p.m. This feature, when utilized, relieves the user of the burden of programming the VCR each week.
Each of the above described VCR features is programmed by the user when the user is in proximity to the VCR. For example, the user can program the VCR by pressing buttons on the VCR. Alternatively, the user can program the VCR by pointing a remote control device at the VCR while following a script appearing on an accompanying television set. A conventional VCR, however, does not provide the user with the ability to program the VCR when the user is not proximate thereto.
For example, if the user of the VCR is away from home when the user remembers that the user forgot to program the VCR to record a particular program, the user may then attempt to get home in time to program the VCR, or may elect to miss out on the user""s favorite program this week. In another example, a user may be at someone else""s house for a party, and may realize that the noise and activity of the party are preventing the user from seeing an important show or sporting event. If the user""s VCR is not previously programmed to record the important show, the user has a choice of leaving the party to watch the show and/or program the user""s VCR, or to miss the important show. In yet another example, a user may be away from home when the user remembers that the user left an important tape in the user""s VCR, and that the VCR is programmed to record an upcoming show. According to this scenario, the user""s VCR may record over the important tape unless the user can get home in time to reprogram the VCR. In each of these scenarios, the user can benefit from the ability to program the user""s VCR when the user is not proximate to the user""s VCR, such as when the user is not at home.
According to the invention, a user can program the user""s VCR when away from home by calling the user""s home telephone number and remotely interacting with a telephone answering device which is adapted for programming the VCR in accordance with the invention. A telephone answering device according to the invention thus includes an incoming call signal decoder adapted to decode a signal contained within an incoming call, and an output device adapted to output a control signal to a remotely controlled device in response to the decoded signal. In an alternative embodiment, a method of programming a video recording device includes steps of calling, from a telephone at a remote location, to a telephone answering device, and providing a programming signal to the telephone answering device, wherein the telephone answering device responds to the programming signal to program the video recording device. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to the manufacture of semiconductor devices with a depletable multiple-region semiconductor material that provides a voltage-sustaining space-charge zone when depleted, and to a method of fabricating such a material. The invention also relates to other semiconductor material and semiconductor devices produced by such methods.
The voltage-sustaining space-charge zone results from charge-carrier depletion of interposed p-type and n-type regions that form multiple p-n junctions in the material. The intermediate dimensions (width or thickness) of the interposed p-type and n-type regions need to be small enough (in relation to their dopant concentrations) to allow depletion of the region across its intermediate dimension without the resulting electric field reaching the critical field strength at which avalanche breakdown would occur in that semiconductor. This is an extension of the famous RESURF principle. Thus, the depletable multiple-region material may be termed “multiple p-n RESURF” material. In the voltage-sustaining zone formed of first regions of one conductivity type interposed with second regions of the opposite conductivity type, the dopant concentration and dimensions of the first and second regions are such that (when depleted in a high voltage mode of operation) the space charge per unit area in the first and second regions balances at least to the extent that the electric field resulting from the space charge is less than the critical field strength at which avalanche breakdown would occur in that zone.
The photovoltaic solar cell industry is extremely cost sensitive, and the cost of a starting silicon wafer is typically nearly half of the value of the finished photovoltaic module. Thus, in this industry it is extremely important that the silicon wafers are used as efficiently as possible. Most photovoltaic solar cells are manufactured by processes on the major surfaces of the silicon wafer, resulting in a depletion zone(s) parallel to the major surfaces. Efficiency of the conversion of light to electron-hole pairs is maximized at the depth of the depletion zone, but is considerably less at other depths. High-purity silicon crystal offsets some of these losses by providing an extended diffusion length, but is more expensive to produce and still has deep regions that poorly contribute to electron-hole pair conversion. Depth of light conversion is also strongly related to photon energy (wavelength), resulting in losses of otherwise useful parts of the solar spectrum.
U.S. Pat. No. 6,703,292 (Grover) discloses a method for producing semiconductor devices with depletable multiple-region (multiple p-n junction RESURF) semiconductor material comprising alternating p-type and n-type regions which utilizes patterned Neutron Transmutation Doping (NTD). Grover's method is an improvement over previous procedures, and uses a collimated beam of thermal neutrons and a neutron-absorbing mask in close proximity to the semiconductor material. Two problems exist for Grover's method; one, thermal neutrons are not easily collimated, and two, masks have large feature sizes as a result of their manufacturing methods. Such large feature sizes are carried into the semiconductor material and exacerbated by diffraction effects at the edges of features in the proximity mask. Similar limitations occur in the exposure step in x-ray proximity lithography, which has most of the same elements as described in Grover's method.
The standard approach for collimating x-rays used at synchrotron facilities, which is to provide great distance from a small origin to the work necessary for proximity lithography, is not effective for thermal neutrons. Thermal neutrons are “produced” in moderating material, such that fast neutrons are slowed to thermal energies via scattering reactions. Consequently, the neutron flux is distributed throughout the moderator and any neutrons leaving the moderator do so with random angular direction. Collimating the exiting thermal neutrons via transmission grids and/or a reduction apertures results in a significant flux reduction. Additionally, thermal neutrons are relatively slow moving, heavy particles with flight paths that are affected by gravity. Grover does not state any method for producing a collimated beam of thermal neutrons sufficient to transmute silicon atoms to phosphorus in a pattern, and it is unclear if the invention has ever been practiced.
In contrast to the exposure step in proximity lithography, which is similar to Grover's method for patterned neutron transmutation doping, exposures in projection lithography are controlled by focusing optics. In this more common process, ultraviolet radiation exiting absorbing masks with large features sizes are projected and demagnified by optical components. In addition to the obvious benefit of imprinting small features, the projection method also reduces the requirements for collimated illumination and controls for mask-edge diffraction effects. It is standard practice in optical projection lithography to have multiple exposures to produce a precise pattern. Prior to this disclosure, no neutron optical projection lithography methods have been proposed for Neutron Transmutation Doping (NTD), a common bulk material doping process.
Photovoltaic (PV) cells are semiconductor devices that convert light to electrical voltage, and are generally made of doped silicon material. Typically, p-type doped silicon is produced as a wafer or substrate onto which n-type doped silicon is deposited. A depletion zone forms in the region of the p-n junction, as discussed above. Photons of light that are absorbed in the depletion zone contribute to the cell's electrical current at nearly 100% probability, as the electron-hole pair are quickly swept apart by the electric field and are collected. Away from the junction, the collection probability drops off. If the carrier is generated more than a diffusion length away from the junction, then the collection probability of this carrier is quite low. Unfortunately, most photons are absorbed in regions that are shallower or deeper than the depletion zone and overall light-to-electricity efficiency is reduced.
The nature and magnitude of a material's band structure are parameters which influence the electronic and optoelectronic devices fabricated therefrom. For example, diodes made from semiconductors with wide bandgaps will tend to have higher breakdown voltages because these materials will have fewer thermally-generated charge carriers at any given temperature and therefore will be less susceptible to avalanche effects. Gallium arsenide will be a material of choice for radiation-generating devices because it has a direct bandgap. Silicon, on the other hand, has been considered fundamentally unsuitable for use as an emitter of radiation. This is because silicon is an indirect bandgap material in which fast, non-radiative recombination processes completely dominate the much slower radiative recombination processes. Indeed in bulk silicon, at room temperature, radiation emission is almost entirely absent.
With the continuing and rapid development of computer processors, the constant demand for increased processing power and speed and reduced size necessitates an ever increasing complexity of the interconnecting metallisations. It is anticipated that this complexity will eventually present an insurmountable obstacle to further development (the breakdown of Moore's Law) because electrons will spend a disproportionate amount of time in the metallisations instead of in the components they interconnect, thereby curtailing processing power and speed.
Optoelectronic circuits based on silicon technology offer a way forward because optical coupling is many orders of magnitude faster than connections based on the diffusion of charge carriers. However, this approach requires development of an efficient room temperature radiation-emissive device based on silicon. Clearly, such a device could be used to enhance the functionality of other silicon devices and could lead to implementation of all-silicon integrated optoelectronic systems.
Prior techniques for making a silicon-based optoelectronic device include porous or nano-particle silicon, or multilayer compound semiconductors, either of which is not bulk silicon. Some attempts of ion implantation to form strain fields within silicon have had limited success, with poor focusing at higher energy/penetration depths being the main drawback (Homewood et al, U.S. Pat. No. 7,274,041).
It is obvious that a method is needed for producing closely matched and closely spaced p and n type doping for vertical devices. It is also obvious that more economical vertical devices manufactured from less pure silicon crystal, polycrystalline silicon, or hydrogenated amorphous silicon is needed. It is also obvious that a more efficient photovoltaic cell is needed, particularly a photovoltaic cell that has uniformly high contribution to current for carriers created at all vertical depths within the semiconductor material. It is also obvious that optoelectronic devices manufactured from silicon crystal would be advantageous. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to data management within a virtual execution environment (VEE), and more particularly, to dedication of one or more VEEs for serving as a network interface for remote users.
2. Background Art
Network administration services for computer systems are typically implemented by network interfaces located on the edge of a local area network (LAN). The network administration includes security services provided for all of the computer systems “behind” a firewall. Another typical implementation of network administration services is to have a network interface having security application, such as anti-virus or spam filtering, executed on each of the computer systems.
Computer systems, such as those that run server processes, typically have a set of services (sometimes called “daemons”) that are used for servicing user requests and operating system requests. These services can be dedicated to servicing requests from external anonymous users, for example, a WWW service or an anonymous FTP service. They can also be used for servicing requests from authorized users, such as FTP service and email service POP3/IMAP4 (Post Office Protocol 3/Internet Message Access Protocol (version 4)).
For management (administration) of the network services, typically a system administrator is necessary, who can enter appropriate operating system commands, and who can monitor the state of the operating system and the services. A particular example of a system administrator is an operator, who is typically allowed only a highly restricted subset of functions—for example, checking server statistics, management of print queues, etc.
The cost of a system administrator for the owner of such a system (e.g., a data center) is often a substantial part of the total cost of ownership (TCO). Easing the burden on such a system operator and enabling a substantial commonality of his activities is an important issue in software development for data center administration.
The job of an administrator, as it relates to administrative services, often includes not just direct commands to the computer system for performance of specific actions, but also involves certain “indirect” operations. Examples of such indirect operations include assurance of an appropriate level of security, verification of system state, backing up data and creation of backup databases, provision of new servers and services, load balancing, etc. Attempts to ease the burden on the operator for providing such functions take several forms.
For example, the use of Virtual Private Servers (VPSs) allows at least some commonality among the various server processes running within the computer system, and also allows commonality in their instantiation and configuration. Usually VPSs are installed with mass administration tools, for example, Virtuozzo™ VPS (available from SWsoft, Inc., www.swsoft.com) has a set of special scripts, command line and Graphical User Interface utilities for such a purpose.
The problem of administration of a large set of services and servers for many users is widely known, especially to administrators of web hosting companies and data centers. Each routine operation often requires expensive manual operations, and, when handling thousands of users even on single hardware box with a single operating system, each simple operation, which should be performed hundreds and thousands of times, becomes very expensive. Unification and simplification of mass operations therefore can result in a significant economical benefit.
Another ever-present problem is assuring a level of safety and security of the services provided to the users. For example, authentication of users and user login verification has to occur within a safe environment. Any failures and crashes of services for one user should not affect services for other users, and should not affect overall system security.
The concept of a so-called “sandbox” is one conventional solution. For example, in the UNIX environment, it is common to place the FTP services for anonymous users within a “sand box.” In that case, even if an intruder manages to gain access to that particular server and “breaks it,” then his malicious activities still occur within the sand box (a secure environment), and the intruder cannot gain access to any critical system data in this fashion.
Additionally, there may be issues with execution of non-standard operations. One type of such non-standard operations is “dangerous” operations that can result in an unpredictable state of the system. Examples include remote services reboot and remote firewall configuration operation. In the case of remote services reboot, should that process fail to reboot and reinitialize the appropriate server process properly, the only recourse available to an administrator of that particular process (for example, to a remote VPS administrator) is to request expensive manual intervention from the system administrator. In the case of remote firewall configuration, the person configuring the firewall could accidentally mis-configure it in such a manner that even the administrator or operator of such a firewall is himself blocked from any further access through the firewall. This results in a server process or a VPS, that is “empty,” i.e., running “normally,” but is in reality useless, because it is inaccessible.
Other non-standard operations include organization of services providing name-based hosting for web users, where a number of virtual web servers share the same IP address with a single logical instance of webserver. Other services include security services.
Accordingly, what is needed is a system and method for providing a more secure and more efficient mechanism for network traffic processing services in a multi-server environment. | {
"pile_set_name": "USPTO Backgrounds"
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Human skin aging occurs at different rates, with some individuals showing fewer signs of aging than others, despite variations in environmental conditions. Current corrective measures mainly focus on smoothing the surface microtexture of the skin, decreasing perceived pigmentation irregularities, and reducing the appearance of lines and wrinkles. For deeper lines, wrinkles, and macro folds of the skin, the use of fillers has come into common use. The upper and lower thirds of the face, along with the neck, have received the most attention, with procedures now being developed for the midfacial areas. Injectable fillers and stimulators are used mainly to replace volume in an aging face, commonly with autologous fat transfer and grafting. Enrichment of grafts for adipocyte-derived stem cells is now seen as a step toward better long-term success; however, given their multipotent nature, a certain degree of caution may be needed in attempting to stimulate differentiation for enhancement of adipocyte number and lipid accumulation.
In addition to filling voids in the face, a comprehensive anti-aging approach can include resurfacing with chemicals, lasers, and microdermabrasion, as well as stimulating the restructuring of the extracellular matrix with topical active ingredients and energy sources such as thermal, light, ultrasound and radiofrequencies. Methods developed to document the aging face primarily focus on the shape, color and texture of the facial skin and its thickness. However, one aspect of aging facial skin remaining to be adequately targeted is pan-facial subcutis lipoatrophy (FIG. 1), or the loss of bulking supportive fat lying beneath the dermis in general. | {
"pile_set_name": "USPTO Backgrounds"
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Bi-directional rings are used in data communications systems to provide high-speed data transmission with a number of safeguards to ensure fault tolerance. Optical networks using bi-directional rings are used in such data communications systems, but a great deal of overhead is associated with converting signals into the proper format required by most optical ring systems.
Other problems with prior art optical bi-directional networks are associated with the routing of data when a fault occurs in the system. When multiple channels of data are being sent over the optical. media, it is difficult and expensive to individually control the routing of the channels when a fault occurs. This is because in prior-art systems each channel must have its own fault detection and rerouting circuitry.
For these reasons, a need exists for an optical bi-directional ring communications system that simply and efficiently provides a means of detecting faults in the media, allows for the adding and dropping traffic to and from the media, controls routing of signals in the network, and provides a maintenance channel, wherein such a ring is also compatible with equipment currently in use. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to convertible furniture and more particularly to a convertible picnic table and bench which is characterized by simplicity and convenience of construction and operation, strength and durability, and comparative low cost of manufacture. In one mode of use, a broad horizontal picnic table top is supported stably between two parallel bench sections at an elevation below the table top and being coextensive lengthwise therewith. In a second mode of use, the two bench sections move together horizontally to form a broad continuous bench or seat bottom and the top of the table assumes a stable inclined position above the bench bottom to serve as a back rest.
While convertible furniture of various types is known in the prior art, no known prior art structure possesses the construction and mode of operation of the present invention or satisfies the need in the art which the present invention seeks to satisfy. On small home patios or porches and on the balconies of high rise apartments, there is a genuine need for a convertible furniture unit of this type and the prior art cannot satisfy this need in any practical or attractive manner.
Other features and advantages of the invention will become apparent during the course of the following detailed description. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a trailer gooseneck apparatus and particularly for interconnecting of a low-boy trailer to a truck tractor.
Commercial trucking includes semitrailer systems wherein a truck tractor is releasably coupled to a trailing load carrying trailer for over the road transport of loads. A low-boy trailer is widely used for transport of off-road construction equipment, such as graders, shovels and the like. The trailer has a flat bed supported at the trailing end by one or more sets of tired wheel supports. A gooseneck apparatus releasably connects the free forward end of the flat bed to the tractor for over-the-road movement.
A particularly satisfactory gooseneck apparatus is shown in applicant's copending application entitled "Trailer Gooseneck Apparatus" which was filed Dec. 16, 1980 with Ser. No. 06/217,050 now issued to U.S. Pat. No. 4,390,192 on June 23, 1983. The gooseneck apparatus includes a horizontal section having a releasable pivot connector for connection to a truck-tractor and a vertical section including a unique releasable entrance support and connection assembly with the trailer. The vertical section is pivotally interconnected at its forward or tractor end to the understructure of the horizontal section and extends rearwardly beneath the horizontal section. The trailer ends of the horizontal section rests upon the vertical section and the sections are interconnected by a powered actuating means such as hydraulic cylinder units pivotally interconnected to two sections. The lower end of the vertical section is coupled to the low-boy trailer by a combination of horizontal and vertical pin-like connections. A horizontally extended pin and slot connection provides a vertical support with releasable interconnection of the trailer to the tractor. A vertical pin and slot coupling allows corresponding connection of the trailer to the vertical section of the gooseneck. A pivotally mounted load structure, preferably in the form of a plate in the vertical section, is movable with respect to the horizontal section to establish a collapse of the vertical section during the attachment and detachment of the trailer without requiring relative motion between the truck tractor and the trailer bed. The attachment and detachment is established without relative movement between the trailer bed and the tractor.
A simple and reliable coupling includes a pneumatic operated coupling pin interconnected to pin opening connection. The trailer includes a coupling opening which is aligned with a mating coupling pin. A spring return means urges the pin into the coupling position. The pneumatic unit is actuated to withdraw the pin from the vertical opening.
Although the above gooseneck apparatus has been found to provide a highly effective and reliable connection, some concern may arise with respect to the reliability of the trailer connection if proper care is exercised in operating the system or constructing the apparatus. Thus a possible separation may arise if the coupling pin is not properly set or if the pin should retract against because the spring load provided is not proper for particular harsh road conditions. Although heavy spring loading may be provided, this requires a corresponding larger releasable motor means. | {
"pile_set_name": "USPTO Backgrounds"
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Historically, insulated pads known as hot mats have been used in the serving of casserole dishes or cookware, (oven heated or refrigerated). The pads are generally square or round, and include some type of an insulation material. Additionally, in the past, cooks have used insulated gloves such as barbecue gloves. These mats and gloves are wrapped around the edge of a casserole to hold it when removing it from the oven and carrying it to the table.
When the hot casserole is placed on the table, it is normally desirable to have some type of insulated material between the casserole and the table to prevent burning and discoloration of the table surface. This is accomplished with trivets of various types which hold the casserole above the table, thereby allowing the hot dish to be readily accessible but out of direct contact with the table. While trivets are generally constructed from rigid materials, there are also fabric receptacles adapted to receive dishes. These receptacles sit directly on the table, separating the casserole from the table by only the fabric material.
One drawback in the prior art devices is that there is no provision made to help retain the serving temperature of the contents of the dish, whether hot or cold, during the time the dish is on the table.
Moreover, with the prior art receptacles being in direct contact with the table surface, the table surface is subjected to water damage due to the wetness or condensation from the dish being served.
Further, the prior art makes no mention of or provision for easing the passing of the dish to others seated around the table.
Accordingly, it is an object of the present invention to provide a method and apparatus for allowing both hot and cold cooking dishes to be easily an conveniently transported to the dining table.
It is a further object of the present invention to provide a means to protect the table surface from a hot or a cold dish placed on the serving table.
It is a still further object of the present invention to provide a means of easily passing the serving dish for serving diners.
It is another object of the present invention to provide a means to maintain the temperature of a dish.
It is a still further object of the present invention to provide a fabric cover to the device that can be easily replaced. | {
"pile_set_name": "USPTO Backgrounds"
} |
It is well known that photographic films can suffer from deleterious effects owing to excessively close contact between adjacent layers of film or between a layer of film and an attached layer of a second flexible material, for example a paper strip backing in the case of roll film. These deleterious effects take the form of sticking, or blocking, of one layer to another or merely of a tendency to accumulate an electrostatic charge which is dissipated when the two layers are separated. In the latter case a visible discharge of light can arise which can fog the film.
It is therefore well known to incorporate in one or more layers and on one or more sides of the photographic film, an antiblocking agent in the form of finely divided hard particles, either of a mineral or more usually of a polymeric nature. Most typically these particles are spherical and often their particle size is closely controlled, since it is well known that very large particles (e.g., having a diameter of about 10 micrometers or more) may be readily seen in photographic prints prepared from the photographic film in which the particles are included. However, a particle size of about 2 to about 8 microns is necessary in order to achieve a useful separation effect between two adjacent film layers, which requires that typically between about 1 and about 7 microns of the particle diameter protrudes from the film.
Owing to the relatively large size of the above-described particles, it is quite commonly found that when such a film is printed, an effect known as "Starry Night Effect" is observed. It consists of a series of visible images of the antiblock particles themselves. This effect may be particularly noticeable when the refractive index of the antiblock particle is very different from that of the photographic coating layer in which the particle is embedded. | {
"pile_set_name": "USPTO Backgrounds"
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Many individuals enjoy decorating their homes and/or offices during times of holiday observance to inspire good cheer and joy, to acknowledge religious obligations, and as a way to celebrate. Specifically, the tradition of decorating a Christmas tree has long been held in western cultures.
The Christmas tree, decorated in ornaments of wonderful variety, has come to be a symbol of the holiday season. It is, however, also a safety concern for parents of young children and or owners of pets. Currently, decorations and ornaments are attached directly to a Christmas tree, typically by string or hook, in such a way that renders the ornament secured to the Christmas tree so that the ornament will not easily detach from the tree. This dated way of attaching ornaments creates a hazardous situation for young children and/or pets who may pull, swat, and/or otherwise attempt to remove an ornament because the attached ornament is fastened securely directly to the branch; rather than be removed from the tree or other fixture easily when disturbed it can pull the entire tree or fixture down onto the child and/or pet, which can lead to injury and/or other damages.
Further, often the joy of decorating a Christmas tree both inside the home and outdoors, has lessened as many people have an ever growing list of obligations. The time spent attaching each individual decorating to each individual branch is extensive, especially considering the short duration of the season. Additionally, the mounting of ornaments to a Christmas tree and other fixtures or items can be physically difficult for any individual who lacks dexterity in the hands and fingers.
For these and other reasons, the present invention is ideal for attaching, assembling, joining, adhering, hanging, mounting, linking, and/or securing decorative accessory, ornament, cover, disguise, and or enhancement to Christmas trees, other items, and/or other fixtures. The present invention allows for the decorative accessory, ornament, cover, disguise, and or enhancement to be attached, hung, mounted, linked and/or secured while allowing for quick release and re-application should the need arise. Further, the present invention reduces overall assembly time of a fully decorated Christmas tree, other items, and/or fixtures in future or subsequent applications.
Decorative accessory, ornament, cover, disguise, and or enhancements are manufactured out of myriad materials and in a variety of shapes, sizes, colors, and/or designs dependent on each individual brand and manufacturer. Any design and/or material of the decorative accessory, ornament, cover, disguise, and or enhancement manufactured and sold under any brand is compatible to the correct use, application or enjoyment of the system apparatus and method of the present invention as described in this application. The method, system and apparatus of the present invention as described in this application can be correctly used, applied or enjoyed with any Christmas tree, whether live, fresh cut, or artificial; other items, and/or other fixtures.
Creating a safe, easy method, apparatus, and system to link, attach, secure, mount and/or join a decorative accessory, ornament, cover, disguise, and or enhancement to a Christmas tree, other items, and/or fixtures was a challenge because the ornament must remain secure unless pulled or otherwise displaced by a person or animal. More over, the method, apparatus, and system, needed to be quickly and easily re-assembled when displaced. Finally, total ease of use for all facets of the method, system, and apparatus was a concern for the end consumer. Also challenging is the differences in the width and thickness of Christmas tree branches, other items, and/or other fixtures one might choose to decorate or enhance using the present invention. The difference in size makes it difficult to design an apparatus, system, and method with the capacity and capability of fitting any type of tree branch, whether live, freshly cut, or artificial, or other item or fixture regardless of size or shape. | {
"pile_set_name": "USPTO Backgrounds"
} |
According to the prior art, to enable electronic devices to be capable of performing communication in various forms, the electronic device is equipped with a plurality of communication chips therein. In this regard, the communication chips are of two types, namely near field communication chips and far field communication chips, depending on the communication distance.
In general, near field communication refers to transmitting data for a short distance (for example, 10 centimeters˜10 meters), whereas far field communication refers to transmitting data for a long distance (for example, longer than or equal to 10 centimeters). Hence, when it comes to data transmission performed by an electronic device, near field communication requires less power than far field communication.
In general, near field communication involves creating a near field communication path by means of the contact of induction coils, whereas far field communication requires no contact but involves matching an electronic device with another electronic device which serves as the destination of the data being transmitted.
Accordingly, it is imperative to provide a device that overcomes the aforesaid drawbacks of the prior art. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to the field of wagering games, wagering games with display of random outcome event generators and wagering games with three-dimensional displays of random event outcome generators in an auditorium or stage setting.
2. Background of the Art
Casinos provide many different gaming formats and many different game events. The various gaming events can be provided in various physical gaming table formats (e.g., roulette, blackjack, poker variants, craps, candy wheels and the like), electronic gaming table formats, electronic video gaming systems, and mixed electronic and physical gaming element formats (e.g., playing cards and electronic wagering, physical roulette wheels and player wagering terminals, player cast dice and electronic wagering terminals, mechanically cast dice and electronic wagering terminals). Except for the ability in video wagering systems to swap active gaming engines on a processor, each of these games require dedicated gaming tables and associated apparatus. This need for dedicated physical apparatus is expensive and requires large areas for placement of apparatus for a single game. The physical gaming systems are also quite limited in their appearance and have maintained a traditional look in spite of the availability of more modern technologies.
U.S. Pat. Nos. 8,172,400; and 8,177,368 (O'Connell) and U.S. Pat. No. 8,034,263 (Maass) describe systems and apparatus useful in three-dimensional staged productions. Included may be any of an image projection apparatus comprising: a first projection device arranged to generate a virtual three-dimensional image; a second projection device arranged to project a background image; and means to minimize transparency of the virtual image relative to the background image; wherein the first projection device comprises a projector, a frame, and an at least partially transparent screen: the frame being arranged to retain the screen under tension, such that the screen is inclined at an angle with respect to a plane of emission of light from the projector; the screen having a front surface arranged such that light emitted from the projector is reflected therefrom; and the projector being arranged to project an image such that light forming the image impinges upon the screen such that a virtual image is created from light reflected from the screen, the virtual image appearing to be located behind the screen. An image display apparatus, comprising: an image source, a mount, an at least partially transparent screen, and a pigmented reflective member, the mount being arranged to retain the screen under tension, such that the screen is inclined at an angle with respect to a plane of emission of light from the image source; the screen having a front surface arranged such that light emitted from the image source is reflected therefrom; and the image source being arranged to provide an image such that light forming the image impinges upon the screen such that a virtual image is created from light reflected from the screen, the virtual image appearing to be located behind the screen, the apparatus further comprising a stage, and a stage background, the screen being provided in front of the stage, wherein a plurality of light sources are arranged to illuminate at least part of at least one of the stage or stage background, and the pigmented reflective member being provided in an optical pathway between the image source and the screen and being operative to reflect only light from part of the visible spectrum such that the pigmented reflective member reduces a milky hue associated with light where there is no image to be presented surrounding a Pepper's Ghost image to compensate for variations in levels of unwanted light hitting the surface of the screen; wherein the screen is a polymeric transparent foil that is held taught and substantially wrinkle-free by the retention members, the retention members having generally parallel faces which clamp an edge region of the foil between them, and wherein individually variable foil tensioning mechanisms are provided at spaced apart locations around the periphery of the foil to enable the foil to have tensioning force independently varied at the said spaced apart locations around the periphery of the foil, and wherein the retention members are connected to one or more flexible tensioning means, which extend from the mount, the foil, flexible tensioning means and the mount lying in a common inclined plane, with the tension on the foil being applied in the plane of the flexible tensioning means and the foil; first and second of the retention members are provided to grip the screen, the retention members having respective openings therethrough arranged to collocate with openings in respective jaws of clamping members attached to tensioning straps; and the tensioning straps are attached to a truss arrangement are adjustable such that the tension of the screen within the truss arrangement can be varied about the periphery of the screen, and wherein the retention members are substantially parallel to truss members comprising the truss arrangement.
U.S. Published Patent Application Document No. 20110319152 (Ross) describes gaming devices, gaming systems, methods of conducting a wagering game, and computer programs for initiating a wagering game are presented herein. A gaming device is presented that includes a wager input device for receiving wagers from players to play a wagering game, and a display for displaying outcomes of the wagering game. The gaming device also includes a multi-layer composite lighting assembly with a first light-emitting layer, a second light-emitting layer, and a spacer. The first light-emitting layer emits light of a first color in a first direction, whereas the second light-emitting layer emits light of a second color in a second direction. The spacer, which is interposed between the first and second light-emitting layers, diffuses and focuses light emitted by the second light-emitting layer through the light emitted by the first light-emitting layer to thereby create a three-dimensional simulation of a component of the wagering game.
U.S. Published Patent Application Document No. 20110281628 (Sieka) describes an outcome of a dice throw and an orientation of the dice can be randomly determined. Based on knowledge of the outcome of the dice throw and the orientation of the dice, die faces that face the player at a beginning time instant of the animated motion can be back calculated. The dice can then be accordingly constrained to a selected one of a number of predefined animations for the dice to efficiently generate a more realistic and accurate graphical representation of the dice throw on the wagering game machine. Such a technique for generating the graphical representation of the dice throw based on 3D modeling and physics of the dice throw precludes managing and maintaining texture maps. Also, the graphical representation of the dice throw can be presented without texture swapping and with less computation because the pre-modeled dice are constrained to the selected animation of the dice.
U.S. Pat. No. 7,922,589 describes electronic game tables with multifunction legs are described. In one implementation, an electronic multiplayer game table includes a tabletop with player stations for an electronic betting game. Multifunction legs physically support the periphery of the tabletop, while electronic components for playing the betting game are mounted in the multifunction legs. For example, a multifunction leg may contain multiple currency detectors and coinless slot machine-style ticket printers/readers, so that each player at the game table has an exclusive currency detector and an exclusive ticket printer in close proximity. The multifunction legs may also include magnetic or smart card readers for transferring player, banking, and monetary information. In a variation, central control components of the electronic game table are also mounted in the legs. The multifunction legs can eliminate the need for a central support pedestal. This enables efficient under-table cooling schemas and other innovations, such as under-table lighting and a central tabletop holograph space.
Published US patent Application Document No. 20090109175 describes a system for a 3 dimensional (3-D) user interface comprises: one or more 3-D projectors configured to display an image at a first location in a 3-D coordinate system; one or more sensors configured to sense user interaction with the image and to provide user interaction information; and a processor configured (i) to receive the user interaction information from the one or more sensors; (ii) to correlate the user interaction with the image; and (iii) to provide one or more indications responsive to a correlation of the user interaction with the image, wherein the one or more indications comprise displaying the image at a second location in the 3-D coordinate system. A method for providing a 3-D user interface comprises: generating an image at a first location in a 3-D coordinate system; sensing user interaction with the image; correlating the user interaction with the image; and providing one or more indications responsive to a correlation of the user interaction with the image, wherein the one or more indications comprise displaying the image at a second location in the 3-D coordinate system. Computer readable program codes related to the system and the method of the present invention are also described herein.
All references cited herein are incorporated by reference in their entirety to provide enabling disclosure of technical aspects used in the practice of the present technology. | {
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The present invention relates generally to electronic data processing tools and, more particularly, to a method, system, and storage medium for providing web-based electronic research and presentation functions via a document creation application.
The ability to create electronic slide presentations in the workforce has enabled enterprises large and small to provide training and disseminate quality information in a professional and organized manner. Presentation software allows users to mix presentation objects to create effective, high-quality presentations such as reports, classroom lectures, business charts, how-to training, as well as digital animation, audio/video media and similar items. Presentation software provides the functionality to handle various modes of information dissemination such as via a computer screen, a movie screen controlled by a laptop computer, a commercial kiosk, or live computer presentation.
Current technology allows presentation software users to create slides for incremental and sequential viewing of slide objects and limit the user to a one-dimensional presentation format. Existing presentation software and word processing applications restrict presentation to internal references, such as templates, and do not allow such systems to reference external sources that are controlled and sourced autonomically. Further, current presentation software and word processing applications do not provide the inherent capabilities for searching and retrieving archived data that are relevant to the document being created.
With respect to word processing software, a user who is creating the document currently does not have the capability to search for relevant content and incorporate it into the document unless the user first accesses a separate application or search engine.
Accordingly, it would be desirable to be able to enable a user to access and link relevant electronic content either over a network or from archived sources during the creation or editing of documents and presentations. | {
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Optical communication systems transmit data using electromagnetic light signals in optical fiber and/or free space (for example, building to building, ground to satellite, satellite to satellite, etc.). The electromagnetic carrier wave is modulated to carry the data. Optical communication in optical fiber typically involves: generating the optical signal, relaying the signal on an optical fiber (including measures to reduce/mitigate attenuation of, interference with and/or distortion of the light signal), processing a received optical signal, and converting the signal into a useful electrical signal. Transmitters can be semiconductor devices such as laser diodes, producing coherent light for transmission. A number of receivers have been developed for processing a transmitted lightwave optical signal to provide processed optical signal input(s) to one or more photodetectors, which convert light into electricity.
A coherent receiver, such as an Integrated Coherent Optical Receiver (ICR), converts a modulated optical signal into four electrical signals corresponding to an “in-phase” (I) and “quadrature” (Q) optical signal components of the two optical polarization states, vertical and horizontal. These components can be processed to recover the optically transmitted data regardless of modulation type. Together these four output electrical signals carry all or nearly all of the information conveyed by the optical signal. The electrical outputs of the ICR provide the I and Q mixer signals for the two polarizations.
Testing an ICR presents a special challenge in that the output stage is a balanced detector pair often followed by a differential amplifier with differential outputs. The fact that there are four differential outputs (I and Q each for X and Y polarizations), compounds the difficulty. A simple coherent receiver is composed of a local-oscillator laser, an optical coupler, and one or more photodetectors that can be in a “balanced” configuration that cancels photocurrents and eliminates DC terms and the related excess intensity noise.
The balanced detection and differential amplification of the ICR ensure that any signal put into only the signal port or only the Local Oscillator (LO) port of the ICR will be rejected unless it is possible to block one of the photodiodes to break the balanced detection. Although early versions of ICRs allowed physical access to interrupt a light signal and thereby break the balanced detection, this is not possible on modern integrated components, which are instead typically intrinsically sealed. Getting any meaningful signal out of the ICR therefore requires both a signal and a local oscillator input. A problem is that the optical LO input must be phase coherent with the test signal. The precise optical phase of the local oscillator signal will affect whether either one or both of the output diodes are illuminated with the test signal.
Since getting any meaningful signal out of the ICR requires both a signal and a local oscillator input, both the frequency and phase relationship between the signal and local oscillator are important. While it is routine to simply connect two single-frequency lasers, one to the Signal and one to the LO port to get a beat-frequency output at the frequency difference between the lasers, this method is good only for determining the magnitude of the frequency response. The phase response of a coherent receiver is also important. In addition to maintaining 90-degree relative phase between I and Q outputs, the receiver also must have low group-delay and skew variation over modulation frequency as well as good Common Mode Rejection Ratio (CMRR) vs. frequency.
Measuring phase response vs. frequency requires a stable phase reference unless both low and high frequency components are supplied simultaneously with a known phase relationship. For example, a pulsed laser has both low and high frequency harmonics simultaneously. However, the pulsed laser still requires some sort of LO input which creates a very similar difficulty to the frequency domain approach.
Embodiments of the invention address these and other limitations of the prior art. | {
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1. Field of the Invention
The invention is directed to epoxy resin systems, particularly low moisture absorption epoxy resin systems. The epoxy resin systems according to the invention have utility in aerospace manufacture, or other applications requiring resin systems having low moisture absorption and good retention of dimensional properties under hot and wet conditions. Prepregs, composites and resin transfer molding applications incorporating the epoxy resin systems of the invention are also disclosed.
2. Description of the Related Art
Advanced composites are high strength, high modulus materials which are finding increasing use as structural components in aerospace, automotive, and sporting goods applications. Typically, these composites comprise structural fibers such as carbon fibers in the form of woven cloth or continuous filaments embedded in a cured thermosetting resin matrix.
Most advanced composites are fabricated from prepregs, ready-to-mold sheets of fibrous reinforcement impregnated with uncured or partially cured resin. In order to be useful in commercial fabrication operations, prepreg matrix resin needs to have a long xe2x80x9coutlife,xe2x80x9d typically defined as the period of time the prepreg can remain at room temperature and still be useful for making cured composites; that is, the prepreg must remain pliable and retain appropriate tack (stickiness). Pliability is conferred by the resin matrix, which should remain relatively soft and deformable without cracking. Outlife is sometimes referred to herein as xe2x80x9ctack and drape outlife.xe2x80x9d
Resin systems containing an epoxide resin and aromatic amine hardener are often used in prepregs since they possess a balance of properties generally required for such applications. An early resin system extensively used in space applications was based on tetraglycidyl-methylenedianiline [TGMDA] epoxy resin and 4,4xe2x80x2-diaminodiphenylsulfone [4,4xe2x80x2-DDS]. This system has been used extensively in aerospace primary and secondary structures.
As a hardener, DDS has a low level of reactivity with epoxy resins at room temperature, and prepregs made using DDS-based systems have good out-life. The resulting fiber composites have high compressive strength, good fatigue characteristics, and low shrinkage during cure. Most epoxy formulations, including TGMDA, tend to absorb moisture (hygroscopic) which reduces their high temperature properties. Accordingly, there continues to be a need for resin systems and composites having reduced moisture absorption.
Other disadvantages associated with prior art epoxy/carbon fiber prepregs are a tendency toward brittleness and microcracking, and high cure temperature requirements, typically in the neighborhood of 350xc2x0 F.
Typical state-of-the-art resin systems for aerospace applications include polycyanate-based resin systems. These resin systems exhibit relatively low moisture absorption, moderate to high toughness, low microcracking, and low dielectric constant. However, the high cost of polycyanate resins relative to epoxies is a disadvantage. Moreover, polycyanates are sensitive to moisture before cure, which makes special precautions necessary, such as the need to predry core materials to prevent blistering and delaminating during cure or postcure. Further, the laminate surfaces of polycyanate-based resin systems resist bonding, exhibit poor tack and drape and exhibit reduced mechanical outlife and storage life. In general, polycyanate-based resin systems require a 350xc2x0 F. cure temperature. Those polycyanate systems having reduced cure temperatures exhibit especially poor tack and drape, and substantially reduced mechanical life and storage life. It has also been observed that, although initial moisture absorption is low for such systems, the moisture absorption in many cases continues to rise during long term moisture exposure and does not reach equilibrium.
It is an object of the present invention to provide an epoxy resin system having low moisture absorption that avoids the disadvantages and drawbacks associated with prior art resin systems. These resin systems are especially suitable for aerospace applications.
The resin system according to the invention has a first component which is generally formed by reacting dicyclopentadiene, epichlorohydrin and phenol to form a polyglycidyl derivative of a phenol-dicyclopentadiene epoxy polymer, and a second component which is an ortho-alkylated diamine hardener.
The epoxy resin of the instant invention has the following structural formula (I):
wherein R is hydrogen or halogen, and n is from 0 to about 0.5.
In a more preferred embodiment, R is hydrogen such that the phenol moiety is unsubstituted, and n is equal to about 0.2. An epoxy resin of this embodiment is available from Ciba-Geigy under the tradename TACTIX 556.
In general, the useful hardeners for the epoxy resin of the invention are aromatic hardeners preferably having a benzene skeleton in which substituted alkyl groups(s) are ortho to substituted amine groups(s).
In a more preferred embodiment, the ortho-alkylated aromatic compound has the following formula (II):
wherein Y is a direct bond, sulfur, oxygen, methyl, substituted methyl, or sulfoxy; R1 and R2 are each C1-C4 straight chain or branched alkyl groups and X is hydrogen, chlorine or bromine.
In a most preferred embodiment, Y is xe2x80x94CH2xe2x80x94, and R1 and R2 are each ethyl. This diamine hardener, 4,4xe2x80x2-methylenebis(2,6-diethylaniline), is available from Lonza Group under the tradename Lonzacure(copyright) M-DEA.
In another preferred embodiment Y is xe2x80x94CH2xe2x80x94, R1 is isopropyl and R2 is methyl. This diamine hardener, 4,4xe2x80x2-methylenebis(2-isopropyl-6-methylaniline), is available from Lonza Group under the tradename Lonzacure(copyright) M-MIPA.
In still another preferred embodiment, Y is xe2x80x94CH2xe2x80x94 and R1 and each R2 are isopropyl. This hardener, 4,4xe2x80x2-methylenebis(2,6-diisopropylaniline), is available from Lonza Group under the tradename Lonzacure(copyright) M-DIPA.
Another group of preferred ortho-alkylated aromatic diamine hardeners is represented by structural formula (III):
wherein the amine groups are meta- or para- to each other, R3 is C1-C4 branched or straight chain alkyl, R4 and R5 are independently hydrogen, branched or straight-chain alkyl or methylthio.
It has been discovered that epoxy resin systems having the above-described dicyclopentadiene-phenolic skeleton and ortho-alkylated diamine hardeners provide low moisture absorption similar to or better than most polycyanate and other state-of-the-art matrix materials, while at the same time providing a desirable combination of other important properties including: low microcracking after thermal cycling, good tack, drape, mechanical outlife, and storage life. The instant resin system is compatible with ancillary materials used in prepreg production, such as metal-containing catalysts which may be present in the release paper. The resin system forms a low, cured-resin density which enables lower weight structures to be utilized. This feature is especially desirable for weight-critical applications, such as aerospace applications. The resin systems are amenable to standard epoxy processing, yielding high Tg and good mechanical properties and very little change in mechanical properties under hot and wet conditions.
In many instances it is possible to provide the instant resin systems at lower cost than state of the art polycyanate resins.
A further surprising aspect of the resin systems according to the invention is their utility in resin transfer molding (RTM) processes. RTM processes generally require lower viscosity resin systems. As described at greater length hereafter, the low viscosity of the epoxidized dicyclopentadiene-phenol/ortho-alkylated diamine hardener resin system of the invention is an unexpected feature, which makes the resin system particularly suitable for RTM processes.
Therefore, in another aspect, the invention is directed to a resin transfer molding process comprising the steps of (a) transferring a resin system into a closed mold containing a fibrous substrate; (b) impregnating the resin system into the fibrous substrate; and (c) curing the resin-impregnated fibrous substrate in the mold to produce a resin transfer molded product, wherein the resin system comprises an (i) epoxy of formula (I) above and (ii) an ortho-alkylated aromatic diamine hardener.
The resin systems of the invention also find utility in the manufacture of prepregs for making composite materials. Composite materials made by resin transfer molding or of prepreg materials according to the invention have utility in the manufacture of spacecraft structures including, without limitation, satellite buses, solar array structures, antennae, mirrors, and reflectors. The composites of this invention can be used as aircraft parts, such as wing skins, wing-to-body fairings, floor panels, flaps, radomes, or automotive parts, as bumpers and springs, and as pressure vessels, tanks or pipes. Potentially, the resin systems, prepregs and resin transfer molding products can be used in any composite structure where low moisture absorption and retention of mechanical properties under hot and wet conditions would be advantageous, including, without limitation, industrial, commercial or military aircraft manufacture, sporting goods manufacture as golf shafts, tennis racquets and fishing rods, and the like.
In addition to the manufacture of composite structures produced by resin transfer molding (RTM), the resin systems of the present invention find utility in vacuum assisted resin transfer molding (VARTM), resin film infusion (RFI), and wet filament winding processes, where low resin viscosity and long pot life, are important.
The inventive resin systems also have utility in adhesives applications, as supported or unsupported films or pastes. The resin systems may further be useful in electronics applications as encapsulation or potting materials. The resins may be useful in applications requiring low dielectric materials where change of dielectric constant with moisture absorption would adversely affect the application, such as in composite radomes.
The resin systems may find use in discontinuous fiber materials or otherwise reinforced composite materials (molding compounds) for compression, injection, transfer, and bulk or sheet molding process applications.
The epoxy resin used in the resin system of the invention, which is set forth in the above formula (I), is based on an epoxidized reaction product of phenol and dicyclopentadiene. This hydrocarbon backbone structure has an extremely low molecular polarity, and the epoxy resins based on this backbone exhibit very low moisture absorption.
The epoxidized phenol-dicyclopentadiene copolymer has a general formula I as follows:
wherein R is H or halogen and n is from 0 to about 0.5. More preferably, R is hydrogen and n=0.2.
A variety of such resins are now commercially available having differing molecular weights and include hydrocarbon epoxy novolac resins known as TACTIX 556 and TACTIX 71756 available from Ciba-Geigy; XD-1000, XD-1000-L, and XD-1000-2L, available from Nippon Kayaku; and HP-7200 and HP-7200H, available from DIC. The lowest molecular weight and lowest viscosity TACTIX 556 and XD-1000-2L grades are most preferred for use in advanced composite applications.
While the above epoxy resins are known to the art, nevertheless when they are combined with contemporary hardeners, such as 4,4xe2x80x2-DDS (diaminodiphenyl sulfone) or 3,3xe2x80x2-DDS, high viscosity mixtures with poor tack and drape properties generally result. Accordingly, significant modification of such resin systems with other low viscosity resins is required to enhance tack and drape properties, which further detracts from the low moisture absorption characteristic of such systems. Surprisingly, the combination of TACTIX 556 and the state of the art DDS hardeners results in a resin system absorbing more moisture than systems in which TACTIX 556 is combined with the ortho alkylated aromatic diamine hardeners according to the present invention.
The diamine hardeners used in the present invention are ortho-alkylated aromatic diamines. While the diamines of formulas (II) and (III) are most preferred, other ortho-alkylated diamines are useful. For example, systems comprising a,axe2x80x2-bis (3,5-dimethyl-4-amino)-p-diisopropenylbenzene, formerly available from Shell under the trade name EPON 1062, are expected to yield good resin systems.
A preferred embodiment of the invention involves the use of a resin system containing the epoxy resin of formula (I) above, such as TACTIX 556, and one or more of the dialkylated diamines of formulas (II) or (III). As is known in the art of epoxy resin formulation, the compositions of these mixtures can be varied, resulting in mixtures with varying epoxide-amine hydrogen molar ratios and concomitant physical, chemical and mechanical properties.
In the resin system according to the invention, relative amounts of epoxy resin (epoxide) and ortho-alkylated aromatic diamine components may be expressed in terms of the equivalents of hardener (amine hydrogen) to epoxy resin (epoxide). An equivalent weight of hardener per epoxide of 1.0 occurs when each of the hardener amine hydrogens is replaced with a bond to an epoxide group. For example, in a preferred embodiment, the epoxy resin is TACTIX 556, which has an epoxide equivalent weight of between about 220 and about 240 g/mol, and the amine hardener is LONZACURE(copyright) M-MIPA, having a molecular weight of 310.49 g/mol. An amine hydrogen to epoxide equivalents ratio of 1.0 is present when the weight percentages of the epoxy resin and the amine hardener are about 74.3 wt % and about 25.7 wt %, respectively. In general stoichioemetric ratios of 50%-130% of the theoretical amine-epoxide hydrogen equivalence are preferred, and stoichiometric ratios of 70%-110% are most preferred.
In addition, the cure cycles used to polymerize the resin system can also be varied, which can result in variations in degree of cure and in physical, chemical and mechanical properties. In general, the resin cure times range between about 1.0 hour and 8.0 hours and the cure temperatures range between about 100xc2x0 and 200xc2x0 C. Because of their low viscosity, long gel time and pot-life, these resin systems are ideal for advanced composite part manufacturing such as RTM and RFI.
Continuous fiber-reinforced unidirectional tapes or woven or non-woven fabric prepregs can be readily produced. Further, the low moisture absorption of these systems makes them especially suitable for manufacture of advanced composite structures for spacecraft.
In accordance with the practice of the invention, the resin formulations described above can be further modified with a variety of materials, singly or in combination, to meet the requirements of a particular process or application. For example, a low viscosity epoxide (epoxide modifier) can be used to increase the tack and drape properties of the resin system. Examples of epoxy materials which can be employed in the resin system include, but are not limited to, Bisphenol F epoxides, such as PY306, GY285, or GY281, available from Ciba, or Rutapox 0158 (Bakelite); phenol novolac epoxides, such as DEN 431, available from Dow, or EPON 160, available from Shell; Bisphenol A epoxides such as Epon 825 or Epon 828, from Shell, or DER332 or DER 331 available from Dow; cycloaliphatic epoxides such as CY179, available from Ciba; glycidyl amine epoxides such as triglycidyl 4-aminophenol (available as MY510 from Ciba or Epon 1076 from Shell), TGMDA, available as MY721, MY9655, and MY9663 from Ciba; Tetraglycidyl-4,4xe2x80x2-methylenebis(2-ethylbenzeneamine) available as MY 722 from Ciba; and others known to those of ordinary skill in the art.
The resin system formulations can also be modified with curing catalysts or accelerators to reduce the gel time, flow characteristics, cure temperature, and/or cure time as desired. Suitable types of accelerators include, without limitation, Lewis acid complexes such as boron trifluoride monoethylamine complex (BF3MEA), boron trifluoride piperidine complex (BF3piperidine) available from Atotech USA, and BCl3 complexes available from Ciba; imidazole derivatives such as 2-phenyl-4-methyl-imidazole (Curezol 2P4MZ) or 2-phenylimidazole (Curezol 2PZ) available from Shikoku Chemicals, and the like, dicyandiamide, substituted urea derivatives such as 3-(3,4-dichlorophenyl)-1,1-dimethyl urea available as Diuron from Dupont, acid salts of tertiary amines, salts of trifluoro methane sulfonic acid, organophosphonium halides and the like.
The base resin system formulations can also be modified with a variety of toughening agents known in the art, including, but not limited to thermoplastics, such as poly(arylethersulfones), available, for example, as PES 5003P from Sumitomo; poly(etherimides), available, for example, as Ultem 1000 from General Electric; or poly(imides), available, for example, as Matrimid 5218 or Matrimid 9725 from Ciba. These toughening agents may be dissolved in the uncured resin matrix or present as undissolved filler particles. In addition elastomers such as 1300xc3x9713, 1300xc3x978 1300xc3x9718 CTBN, which are reactive liquid polymers from BF Goodrich may be incorporated into the resin system by simple blending or chemical prereaction with one or more of the epoxy resin components. Preformed elastomeric core-shell types of polymeric particles are useful and are readily available to those skilled in the art.
Other fillers and modifiers may also be incorporated into these systems to impart other desired characteristics to the resin matrix. These include without limitation fumed silica, available as Cabosil M5 or TS720 from Cabot, Aerosil US202 from Degussa, and the like, which can be incorporated to increase the viscosity and reduce the flow of the resin composition during processing and cure; pigments such as carbon black to color the composition; antimony oxide and/or brominated epoxy resins to impart flame retardant properties; and thermally or electrically conductive materials such as BN, Al2O3, silver or aluminum powders to impart thermal and/or electrical conductivity.
A surprising feature of the present invention is that in general the resin systems containing epoxy resin and diamine hardener according to the invention exhibit a lower viscosity than either of the epoxy resin component or the ortho-alkylated diamine hardener component. This xe2x80x9ceutecticxe2x80x9d-like feature is particularly important since, for example, TACTIX 556 itself is a semi-solid at room temperature and would not ordinarily be expected to form a resin system having a sufficiently low viscosity for use in RTM and prepreg applications. However, when combined with the instant diamene hardener, the resulting system exhibits excellent room temperature viscosity which is achieved without the addition of (plasticizing) components that could ultimately increase the moisture absorption of the resin system.
Low moisture absorption is a critical property of resin systems used in advanced composites for space applications. In such applications it is particularly important that the initial resin systems for forming the prepregs and composites retain their desired properties under hot and wet conditions. To measure moisture absorption a 72-hour boiling water weight gain is determined. As used herein 72-hour boiling water weight gain means the amount of moisture taken up by the resin system when the cured resin system is submerged in boiling water and weighed after seventy-two hours. The weight gain is reported as a percentage, relative to the starting weight.
For the neat resin system, which has not been formed into a prepreg by incorporation into reinforcing material, the desired weight gain is less than about 1.3%. A preferred weight gain range is between about 1.2 and 1.3%. In some embodiments, a seventy-two hour boiling water weight gain of less than 1.2% is possible. When low moisture absorption is critical the lower the weight gain, the better.
Another measure of moisture absorption is weight gain at equilibrium in a 50 percent relative humidity environment. To determine such weight gain a cured resin system according to the invention is oven-dried and exposed to a 50 percent relative humidity (RH) ambient atmosphere at room temperature (RT). The system is allowed to reach equilibrium wherein substantially no water is taken up by the resin system over three successive weighings, and the weight gain of the resin is reported as a weight percentage, relative to the starting weight. Neat resin (i.e. resin that has not been impregnated into a fibrous reinforcement material) according to the invention preferably has a 50 percent relative humidity weight gain less than about 1.0%. More preferably, weight gain under these conditions is less than 0.75% and most preferably less than 0.60%. Again the lower the weight gain, the better.
To evaluate the weight gain of prepreg at equilibrium in a 50% relative humidity environment, 2xe2x80x3xc3x972xe2x80x3 laminate samples were machined and predried in an air circulating oven for three to five days at 250xc2x0 F. The dried samples were weighed and placed into a conditioning chamber maintained at 50% relative humidity at room temperature. Equilibrium is defined as constant weight over three successive weighings. A preferred uncured prepreg according to the invention typically has a 50% relative humidity weight gain of less than 0.40%. In a most preferred embodiment, the weight gain under those conditions is typically less than 0.20%. The seventy-two hour boiling water weight gain of the uncured prepregs is generally less than about 0.50%, more preferably less than 0.40%. The percentage weight gain is with respect to the prepreg, including reinforcement.
Prepregs or preimpregnated reinforcement may be prepared by several techniques known in the art, such as wet winding or hot melt. In one method of making impregnated tow or unidirectional tape, fiber is passed into a bath of the epoxy/hardener mixture. Although unnecessary for most applications a non-reactive, volatile solvent such as methyl ethyl ketone may be optionally included in the resin bath to further reduce viscosity. After impregnation, the reinforcement is passed through a die to remove excess resin, sandwiched between plies of release paper, passed through a set of heated rollers, cooled, and taken up on a spool. The resulting prepreg is used within a few days or may be stored for months at 0xc2x0 F. During prepreg manufacture, the resin system typically xe2x80x9cB-stagesxe2x80x9d, or partially advances through the reinforcement.
Composites may be prepared by curing preimpregnated reinforcement using heat and pressure. Vacuum bag/autoclave cures work well with such compositions. Laminates may also be prepared via wet layup followed by compression molding, resin transfer molding, or by resin injection. Typical cure temperatures are 100xc2x0 F. to 500xc2x0 F., preferably 180xc2x0 F. to 450xc2x0 F.
Manufacturing composites typically involves laying up a number of sheets of uncured resin-impregnated fibrous substrates (prepregs) on a suitable tool or mandrel and subjecting them to heat and pressure in order to completely impregnate the sheets. The treated sheets become molded to the configuration of the mold and are then subsequently gelled (or crosslinked). The resin is then completely cured by further heat treatment in order to fix the resulting configuration of the molded laminate.
The resin systems of this invention are well suited for filament winding. In this composite fabrication process, continuous reinforcement in the form of tape or towxe2x80x94either previously impregnated with resin or impregnated during windingxe2x80x94is placed over a rotating and removable form or mandrel in a previously determined pattern. Generally the shape is a surface of revolution and contains end closures. When the proper number of layers are applied, the wound form is cured in an oven or autoclave and the mandrel removed.
In a preferred embodiment, modified or unmodified resin systems are used in conjunction with continuous fiber reinforcements to produce resin-impregnated unidirectional tape or woven fabric (prepreg) materials, which are subsequently used to produce advanced composite parts. In a preferred embodiment, the resin systems comprise between about 30 percent and about 40 percent by weight with respect to the finished, uncured prepreg.
A wide variety of fiber reinforcements are available and can be used in accordance with this invention, including S-glass and E-glass fibers, carbon fibers, aromatic polyamide (Kevlar) fibers, silicon carbide fibers, poly(benzothiazole) and poly(benzimidazole) fibers, poly(benzooxazole) fibers, alumina, titania, quartz fibers, and the like. Selection of the fiber reinforcement type for these materials is determined by the performance requirements for the composite structure. For many spacecraft applications where high stiffness and low weight are critical, high modulus carbon or graphite type fibers are the preferred reinforcement. Examples of this type of fiber include P75, P100, P125 from Amoco, M40J, M55J, M60J from Toray, and K139c from Mitsubishi.
Alternatively, discontinuous, non-woven cloth, whiskers, chopped fiber and mat-type reinforcement materials may also be utilized.
Another method of making composite materials is by resin transfer molding (RTM). This is a process by which a resin system is transfered while at relatively low viscosity and under pressure into a closed mold with all of the important reinforcements and inserts already in place. The resin system can be prepared by premixing and placing the resin system into a resin injection pot or by metering components from separate pots at the appropriate mix ratio to an in-line static mixer or mixing zone. The resin system is then injected into the mold which is maintained under low pressure or under vacuum. The mold is often filled with resin while under vacuum to eliminate air from the mold space, to assist in resin injection and to aid in the removal of volatiles. The viscosity of the resin system dictates whether pot and/or mold heat is required. Low resin viscosity at the injection temperature is desirable to obtain best mold filling and mold wetting. After the mold is filled, it is sealed and heated in accordance with the appropriate cure schedule. The resulting molded part can then be removed from the mold and post-cured as necessary.
In order to achieve good fiber impregnation and low void content during RTM processing, resin viscosity below about 2000 cps at the injection temperature is highly desired, with resin viscosity below 1000 cps being preferred, and below 300 cps, most preferred. Further, the resin system must maintain this low viscosity for a period of time sufficient to completely fill the mold and impregnate the fiber preform. For RTM processing, such time is frequently measured in terms of the pot life of the resin, which can be defined as the time required for the resin to double its viscosity value. A resin pot life of at least 1 hour, and preferably two hours or more, is generally required for production of parts via RTM.
In another preferred embodiment of the invention, modified or unmodified resin systems as described are used in conjunction with woven fabric or non-woven mat reinforcements or preforms to directly produce advanced composite parts via processes such as RTM, RFI, VARTM. In these processes, the resin and fiber are combined during the actual part molding process. Any of the above listed fiber types may be utilized, with the most preferred type being determined by the performance characteristics of the application.
The following Examples are illustrative of the invention and are not intended to limit the scope thereof, which is defined by the appended claims. | {
"pile_set_name": "USPTO Backgrounds"
} |
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